BUSTEDKNUCKLE, Those sizes you mentioned seem pretty good. That would give you a very slight downward rake. It appears in the pic that all four tires are the same size right now and the truck sits approximately level front to rear. Personally , on a hot/rat rod, I prefer a bit more rubber rake. Something in the area of a 30 inch tall rear tire and a 27 inch front tire. I think as long as you don't put taller tires on the front than you do in the rear, you can't go wrong with that truck though. Very cool indeed.