As a side note : Gel Pack armor mods state they take up [1] capacity in armor, since the capacity can range from [4]-[12] and unfortunately never explicitly states they do not stack with themselves it is relatively easy to grab a armor of 40+ just using Gelpacks (Don't get hit unless you like being knocked down every 5 seconds). However for the sake of this thread we will only put one gel pack per armor piece.
As a side note : All spell hits are taken at a average of what a starting character can normal cast (6), obviously the end results can be higher and will be added in as a side towards the end.
As a side note : All cyberware is standerd grade, Alpha+ can net you more armor
Firstly lets take a look at the character needed to play with this thought in mind effectivly.
There are two ways we can go..
1) Magical
2) Non-Magical
Neither of these two ways are mandatory, being non magical will net you a extra 12/12 armor but you then need a Contact/Ally who can cast spells on you. Vice Versa if you are magical you lose out on 12/12 armor but then have less reliance on other people.
After picking 1 or 2, you then need a character who can have 60k+ Nyuen. (This requirement isn't even mandatory and depending on the game wont be needed at all)
Done, that's all that's needed to have a character with a armor value of 100+, easy isn't it?
Secondly lets take a look at where we get some of our armor from, we will then actually put this information into practical use. A lot of these choices seem easy however a few will surprise you, please bear in mind before crying foul lets see what I can correctly remember. (Keep in mind at this point I neither have my books nor my notes, I will change and update as I get a hold of each)
1) One of the main sources of armor comes from a vehicle, a car to be exact, that one car from Arsenal with 14 mod slots and a body of 10. Taking this vehicle we will add 20 armor and 10 personal armor also Walker Mode and 2 Articulated Arms. There is a rule in the Shadowrun main Book that's states (paraphrased) "When directing a attack towards a target in a vehicle add the vehicles armor rating to the characters total then determine damage as normal" This nets us a total of +30 armor for our character. Sadly being in a car is limits where you can and cannot go, this is why we add the Arms and Walker Mod to the car with this add on you (inside of it) can now travel most anywhere even sewers. Most corporate building/tunnels are large enough to fit a 10-13 foot tall car than can walk, remember you can always kneel

EDIT: you don't need this car ( I think the mental image is awesome though) with a mbit of modding you can get the same stats with a Horseman enclosed bike. You just need to turn it into a drone before you can give it armor 20/20 with that control rig thing. This option is preferred if your GM goes into seizures when you try and explain why the car can enter a building. (Which it can BTW its small enough)
2) Main armor, this can be any armor that has a rating of 6/4 or larger, IIRC coveralls fit this nice but for this thread we will use Riot Control armor since anyone can get it netting us a total of 6/9.
3) Form Fitting full body, has a rating of 6/2 I believe
4) Ballistic Shield x2 (one in each hand, more on this later) this nets a total of 12/8
5) PPP armor which is a total of 2/6 for every piece for a total of 5 items
6) 12/12 for cyber limb/legs/torso/head, this is optional and is not advised for a Magical character, although as mentioned you can still get this option and have people cast spells on you, kinda like having your cake and eating it too. However semi-reliant on others. (More on this later) EDIT: Tack on Titanium Bone lacing IIRC that's another 1/1 for a total of 13/13
EDIT: You can also buy extra armor for your cyberlimbs netting you another 24/24 for a total of 37/37.
7) The armor spell can get you a rating of 1-12, for the purposes of this thread we will take the average of 6, netting us 6/6.
8] The Physical Barrier spell can provide a mobile source of armor with every cast, since it can be shaped to fit any area and the basic rules add the structure rating of a barrier to a characters armor we get a number between 1-12, again granting us 6 for a total of 6/6.
9) A Riggers Cocoon will get us 10/10 (Bet your wondering why I included this, keep reading)
10) Helmet, this will get us 2/2 for the good one, I cant seem to find anything that says the PPP helmet cant be used with a regular one, since the description of PP is it can be "Strapped on" or "Added" to other armor, in reality you get a big...thing on your head that semi resembles a helmet but in practice it stacks

11) Out of all the armor clothing lines only the Shawl/Scarf/Stole can be reasonably added with other armor netting another 1/0. Also before you get upset saying they only stack with other pieces of the line it was produced in, I suggest you go reread that section, they can in fact be worn with any armor. It also makes perfect sense to have a armored scarf over your Security Armor, not only do you LOOK nice you are reasonably protected with added ballistic cloth.
12) One Gel-Pack for each and every peice of armor comes out too... 11/11
EDIT: It has been pointed out that only the Form fitting armor and the Sec Armor can use the Gelpacks, so in order to grab these numbers above (or more) you will have to use all the capacity in both. Since the total is roughly the same I will not alter the final numbers.
13) Assuming you are a Magical character (you are aren't you?) then the Hardening spell can increase the Car's armor by another 1-12 for a once again average of 6 for a total of 6/6.
14) Reserved for when I find my notes.
Thirdly lets look at how all of this mess can be effectively used without being so weighed down you can no longer move.
Side Note : If you chose to take Non-Magical then its easy to use a control rig wireless or whatever it is what hackers do to "Jump in" a vehicle and piolt it, if you chose Magical there is a non essence draining alternative I forget what it is but its in the main book, VR gloves and Helm I believe, more on this when remember.
We take out cool Mecha-Car paint it up nice, maybe add some weapons it doesnt matter. What matters is that you put the Rigger cocoon in it and get in (be sure to take all your armor with you) You can then "jump" into the mach to retain full mobility (actual body/agi score won't matter when your not moving), if you chose Non-Magic then you will need to rely on the Mach to do anything (Shoot stuff or Punch stuff) if you chose Magical you can just cast from inside the Mech using the Optical cables/cameras/whatever it was.
Protecting you're investment : I can't stress how important it is that you Harden EVERYTHING to protect it from EMP attacks, and dont forget to Polarize your mech windows. If you have polarized windows you can target people with spells but they can no longer draw LOS to you making you immune to spell casting directed at you. I believe it talks about it in Arsenal but this info might also be in Street Magic. Active Counter spelling can also be placed on objects giving your car added survivability when weathering a magical onslaught.
This will net you a total of..
99/96 w/out Cyberware or Overchanneled spells (12 hits)
130/127 with Cyberware
148/145 with Overchanneled spells and Cyberware
???/??? with my lost notes, last I remember I was somewhere around 140/150ish.
Assuming you can put multiple gel-packs into a piece of armor until you fill up the capacity ( I haven't found anything that says NO, just common sense is holding me back) Then we can add another 30 points easy to any of the above examples.
Now my character that goes off of everything you just read is fully fleshed and stated out, and spends most of the time in my Knightmare Frame (The mech) named Lancelot (anyone get the reference), however no matter what character you use you should ALWAYS go in the car when possible, assuming you can't for whatever reason its easy enough to walk around with a combination of the above equipment for nearly any number you might want. Lancelot's pilot walks around with a 44 Ballistic armor and 40 Impact armor when a bit more discretion is needed MORE than enough ever needed ever. If you don't want the Car (it costs around 46k Nyuen) then as mentioned you can do without if needed. Its also important to say if you chose Magical you can then simply cast Invisibility or whatever other spell you want help getting around (you can also HEAL your mech with the Fix spell /squee)
As a side note : The Arsenal book gives reiterates one of the older rules from 2nd and 3rd in the guise of Custom Fitted Armor. If you want to wander around I highly recommend you use this as you can get more mileage for your money, and consequently higher amor without being boned by a low body and agi score.