[flyingtim01]

Depends on what you want to do with the truck. Pulling a trailer? Hitting some trails? Maybe want to go with a lower gear. Just cruising on the highway and throwing it in 4WD when the snow starts to fall? Maybe go with a taller gear. Just be sure you know what gears are in the front axle, the ratios have to match so you don't break everything the first time you put it in 4HI.

Rear Dana 60's shouldn't be too tough to find, it's the fronts that are a little scarcer. Though it occurred to me that they're 8 lug, and you're probably 6 lug right now. You should be able to find a 6 lug 12 bolt pretty easily and cheaply, I'd imagine, which should be fine, unless you plan on taking it off road abusing it.