As asked in another thread, here are some idea on changing the vehicular combat rules.

1- weapons have to be tagged as Anti-Vehicular or Anti-Personna. An AV weapon is any weapon able to destroy/disable a vehicule without having to ressort to called shot on critical area. Any LAW or ATG by example. Vehicules can be classified as unarmored, lightly armored and heavily armored. Assault Rifle and LMG could qualify as AV on unarmored target but not on armored one, while MMG and HMG are AV for non or lightly armored target.

2- vehicules should been given a Mobility tracking monitor. And attack could target speciffically this monitor wich benefit from Armor value different from the base vehicule. A tank track by example would rate as lightly armored and thus could be targeted by HMG in order to Mobility kill the vehicule. This monitor will affect Pilots skill test, vehicule speed and manoeuvering test. When destroyed the vehicule stop moving until repaired (easier faster to fix depending on the system)
AV damage would affect both monitor at once (or not, need playtest).

3- when a shoot penetrate a vehicule there should be damage to the cargo, passenger, systems or empty space. Depending of the weapon one or several roll could be made on a localisation table to see the system affected (everything in the case of a exploding warhead).

4- a weapon classified as non vehicular against the kind of armor should ressort to called shoot to aim vulnerable part of the vehicule. Each vehicule list the part that are vulnerable, their armor rating. A wheeled APC, by example would be lightly armored, but with unarmored propulsion, unarmored top AA shooter position, unarmored driver slit when open.

If you want this kind of complexity, go back and play the editions released by FASA. In my opinion, the proposed changes are overtly complicated and make a complicated section of the rules even worse.

Vehicle can have common armor or heavy armor. Common armor follow the normal rules, heavy armor follow the normal rules if hit with heavy weapons, otherwise, all the armor dice are considered as automatic successes. Targeted shots to damage specific components, like tires and sensors, ignore this rule, as usual.

You may want to consult Rigger 2, and its Vehicle Subsystem Damage rules (pp. 85 - 87) (and the largely identical rules in Rigger 3, pp. 77 - 80), and see if that is sort of what you want. Just be aware that AFAIK people rarely bothered with those advanced rules.