Dry paved roads should give you plenty of traction. Stopping will be your biggest problem. Down-shift as needed going up the hills, throttle back at the top of the hills and don't try to go down a hill in a higher gear than it takes to climb that hill. Runaways are a dangerous ride. If your tractor's brakes are not in top condition, or if there is an intersection on a down-hill run, consider down-shifting one more gear before going downhill with a very heavy load pushing you.
Check the tresher's tires and air them up. Maybe jack up the tresher's wheels, lube the wheel bearings or wheel bushings and make sure they spin smoothly before starting out on the road. It may have been 50 or 60 years since those wheel bearings were last checked.
A chase vehicle with the emergency flashers turned on would be a safe idea.