Yikes, this thread brings back memories.
I put my old Dmax GMC 2500 CC/SB on a tandem axle rental trailer once. I thought the poor thing was going to drop to the pavement. It was a real piece too, light-duty axles, no brakes, 2" hitch, c-rated tires, the works. I had to haul the truck from Bakersfield to Mike L's place. Good times . . .
I guess the point I'm trying to get at is: DON'T do that if you can avoid it. Borrow a HD trailer or flatbed from someone if you can.