Ok,,now let me get this straight..he has his frame ridged to the cart hauler, and now he is going to put swivel wheels on the back edge? What happens when you hit a dip in the road? Something has to give..probably his 5th wheel frame I would imagine. There is a solution to his problem which I have. Go to
www.swivelwheel.com and you will find swivelwheel trailers just for the back of 5th wheel trailers. I have a single wheel trailer for my Harley. It works great, and I can back up without jacknife. A simple solution for carrying 4 wheelers, cycles, or golfcarts.