After draining and refilling the rear end I dropped the drive line and loaded up all my tools into the bed (lets just say it was full and leave it at that) loaded it onto a dolly from the U-place and drove from Fresno, Ca to Astoria, Or with no problems. I couldn't get a trailer because they said my G20 van wasn't big enough to handle it. (But a dolly was OK?)
I did check the front tie downs regularly as they tended to worked loose every hundred miles or so. The tires barely fit (as in they were hanging over the edges) but we cruised 65 to 70 up I5 all the way(900 miles).
I did make sure the tires and everything else were running nice and cool the first few miles and again when I was tightening the front tie downs but it was easy peasy and the guys I picked up hitch hiking couldn't believe we were actually towing it as effortless as it was. I don't think I'd try it backwards like the manual says. Nor would I try it on iffy tires (you don't want to ask me why)
Your experience may vary