My current truck has 3.55 gears and about the same height rear tires as yours. With a 4 speed manual, 1:1 4th gear, it runs about 2500 down the highway. That's near the top for my 235, but a 283 will run there in its sleep. With the granny 4 speed, I still have all the low-speed grunt I can use.
Devin
