In the pics of the 2 cars doing wheelies , what looks like rear driveshaft loops are really fromt mounts for the ladder bars /traction bars. Take it from me, the loop should be in front ,alittle behind the u-joint. I have brocken a rear u-joint at a full thottle launch & the drive shaft just falls out on the ground, no problem as long as you have a rev limiter to stop your engine from overreving at the sudden loss of the load. We have also lost the front u joint under a full thottle launch, with front tires in the air, did not pole vault the car but the driveshaft came right through the floorboard of the car , could have killed the driver, but it missed him. It caused ALOT of damage , all the inside Aluminum tin work had to be replaced, along with most of the front tube chassis /suspension. I really belive that under full thottle, with the weight of the car off the nose, cosidering todays strong drivshfts, it would be very possible to pole vault a car if the front u-joint were th break. I now have a loop at the front & rear , plus my ladder bar mounts,running uner the drivshafts on both of my Camaros.
Chris