Tony, the cheapest way to get "longer legs" is to swap out the 5.14:1 for a 4.10:1, which came in later versions of that axle. This will give you a cruising speed around 45-50 mph without straining the motor. If you want better (lower numerical value) than 4.10's you will have to change the whole axle or have a ring & pinion custom made; both options are a huge investment of time and $$$. Think of all the fabrication involved in putting 1/2ton hardware under a tonner frame... if you're going that far you may as well upgrade to IFS and front disc brakes.
