Dave,
The 8x8 had its problems towing, first off it's heavy (16,000 lb plus), and the front wheels didn't follow through in the turns, so it was literally dragged through the turns, which required low 1st gear to move after a stop sign with a right or left sharp turn following.
We suspended the rearmost axle to make turning easier.
It tended to "fishtail" when driving downhill, but by starting out relatively slow (40 mph) before a downhill run, I was able to give it just enough boost to power it downhill and prevent his. Never knew Tennessee had so many ups and downs! Required constant attention to the road. Hated construction zones with no shoulder and cement dividers (Memphis comes to mind).
Interstate driving, slowest uphill speed was about 30 mph, 40-45 on the level ground and about 50 top speed at the bottom of a hill.
Cops never even looked twice, not even when I was "fixing" the blown tire. Drove some 10 miles on the shoulder and no attention from the cops. Never stopped at any weigh stations (most were closed anyway).
Back road driving was murder on the deuce, sometimes 10 mph uphill, rarily more than 25 with all the curves and hills here in VA.
Scale recipt below.