Hello, K -
I just towed my 56 on a dolly - I did drop the driveshaft, but mine is of course an open driveshaft, so it took all of five minutes.
The main reason I did this was to prevent the shifter from bouncing around and popping into gear. I'd heard a few stories about that happening.
An added bonus was reducing rolling resistance.
I also think towing backwards would not be advisable. even if your steering wheel is "locked", there's bound to be a little slop. That will result in the "front end" - the back of your rig - swaying from side to side, and that will get transmitted like a whip up towards the front of your rig.
I had no issues whatsoever using a tow dolly. I was fortunate to have a near-new dolly to use. My terrain, route, conditions, tow vehicle, and other variables are different from yours, though. Just use your head, common sense, and extra doses of caution (and don't be afraid to abandon project) and you'll be fine.
