Truck suspension has come a long way in the last 100 years. Just kidding! It hasn't at all, so this excellent instructable video on how to lift 1969 Jeep Wagoneer with new shocks and springs is probably applicable to your rig.
Hooniverse's Tim Odell does a great job explaining the fairly simple process of putting a lift kit on a truck, and even if he didn't, his classic Wagoneer is pretty enough to make the video worth watching. Make sure you stay for the whole thing to see (his son?) Henry get adorably excited about the noise an impact wrench makes.
If you are going to attempt this yourself your biggest obstacle is probably going to be rusty bolts... for that you're gonna want a lot of penetrating oil (PB Blaster), possibly a torch, and if you live in a road-salt state, a healthy dose of good luck.