Fox, thanks for the link.I guess a good place to start is measuring the rear axle in my truck and then go from there looking for donors with the same measurement.
Sweet, I plan to drive my truck simply for pleasure. I'd like to be able to cruise at highway speeds and to be able to get better gas mileage with much lower RPMs, so a donor rear axle with the taller gear would suit my needs. No dragracing for me! I will only drive it on the weekends to car shows & the like within a 200 mile radius of San Antonio Texas. I have a 1950 1/2 ton that is still all original that serves me well hauling stuff & doing chores around the place.