Trigger documentation? car aiming

After a year of developing with Torque, the trigger (as in guns and jumping) system remains a mystery to me. Is there any documentation out there explaining it?

What I'm wanting to do is develop an aiming system for guns mounted on cars, where the user would hold down the right mouse button, causing control to shift to aiming the gun as opposed to driving. I don't even know where to start! Any ideas would be greatly appreciated.