I am wanting to swap out the gears (3.9) in my original :confused: 55-1st series. It is a daily driver and I need the ability to travel over 45mph on occasion. I have located gears (3.36) from a later model chevy. Any idea how much difference I would see changing from 3.9 to 3.36? Would the diference be worth the trouble of swapping? What would be better? Any ideas welcomed.