Gang warfare, with complications. Options

[FuelDrop]

Hi all.
My group has recently received a commission to stop a gang's aggressive expansion in the northern Seattle Barrens, as the Mafia is afraid they'll encroach on their territory and don't want to send their own soldiers against this unusually well-equipped gang. (The fact that we've gotten something of a reputation for doing the impossible among the mafia didn't hurt our getting the job)

We're getting paid a decent sum for the task, but the real payoff is that our mafia contact has offered us 65% of street value on all loot or salvage from the mission, and anything we want to keep they'll exchange for a newer/better-condition version.

However, there's a reason the Mafia doesn't want to send their own troops in on this: in addition to some solid infantry firepower, the gang has gone and got themselves a pimped-out Devil Rat APC, likely with full armour and smart armour in addition to some big guns. They're using it as an 'I WIN' button against the other gangs, and even our group is going to have some trouble dealing with it in a straight fight.

Naturally enough, we don't want to kill it... we want to steal it! As of right now our plan goes something like this:
1) Steal a car.
2) Armour stolen car up, give it a rigger adaption, add firing ports for our gunslingers and a mounted weapon for our Ninja (who has no hand-held firearms skills but does have gunnery. Don't ask me why).
3) Drive into enemy territory and basically go wild, car-jacking, looting, taking hostages, blowing up strongholds... anything that will demand their immediate and total attention.
4) When the Devil Rat comes on the scope our airborne assets reveal themselves, pounding it with the EMP missiles from arsenal (Zappers, as I believe they're called). These will either offline the APC entirely or just disable the crew... in theory. If neither of the above happen then our backup plan is to have some Anti-Tank missiles (From WAR!) on standby, and if worst comes to worst then we're not too proud to flee and come up with a new plan.
5) With the Devil Rat out of the picture and the local gangs coming together in an alliance (Which I've already negotiated), the new gang's progress should slow significantly.

What we need is a 6) that can completely curve-ball them and either de-claw them completely or just set them back so far that they're no longer a threat. I'm working on something involving the face and the social infiltrator approaching two different lieutenants with offers of support from some mysterious backers (opposing mysterious backers, naturally), then having the ninja sneak in and eliminate the boss with enough ambiguous evidence left behind for both sides to frame the other and thus (Hopefully) turn the gang on themselves. However, we need a plan B (and possibly C) in case that doesn't work.

Suggestions?