There should be minimum requirements to even successfully steal the tank, besides actually getting to the tank. For it to be driven, whatever designated driver you choose should either have been a converted soldier/veteran, or have, let's say level 10 Driving and 10 in Intelligence. Why? Even for a liberal, who, without any previous training with a tank or a good amount of automotive skill/military knowledge/logical ability is going to be able to jump down the hatch of a tank, go to the driver's controls, and move the tank? I would imagine that a tank's controls are more sophisticated than a regular car's. I'm in favor of manning the tank with a squad, but each station should require certain skill levels to be operable by a liberal.
Here's an idea of what a tank's stations could be like if it had six operable (As in useful, not just riding the tank.) stations, along with some descriptions:
Driver:
Requires 10 Driving, 10 Intelligence
The tank is only mobile if there's a driver. The tank can be manned without a driver, but it will serve little use than an armored turret.
Spotter/Commander:
Requires enough leadership skill to command five people, though ability in skills used to run the tank helps it run more efficiently.
Cannon Operator:
Requires 5 Heavy skill.
Takes commands from the Spotter/Commander on what to shoot. Possibly this could give you the option of either assigning a valuable target to be shot at (A part of a building, another vehicle, etc.) or telling the cannon operator to fire at will, allowing them to shoot at enemies.
Machine Gunner:
Requires 10 Rifle skill
Sits at the machine gun and fires at enemy personnel. Has a risk of being fatally wounded, unless they're controlling the machine gun from inside the tank somehow.
Ammo Jockey:
Requires 5 Strength to load the cannon, 10 Agility for the sake of not dropping the damned ammunition.
Fetches and loads the ammo for the cannon and machine gun. The slower he is, the longer it takes to reload the cannon and machine gun.
Sapper:
Requires 5 Driving
Makes sure the tank stays in functioning order. He's also the poor sap who gets to climb out and try to reattach the treads in the event they get torn off, or kick the tank if it won't move.
The tank itself should have health indicators, with certain areas being vulnerable as if it were a normal entity. The weapons taking too much damage should render the unusable, while armoring that has been damaged too much will cause the tank to take more structural damage, as well as letting some bullets fly in and potentially wound the passengers. There should be a "body part" called the chassis that takes injury from heavy attacks, or when attacked after armor has been degraded.
And of course if you just want to be a pussy about it, you could use the tank as an APC and some of your Liberal Team Six units can ride inside and some can ride outside, and it can be used to breach buildings and as cover during sieges.