What do you need? You'll need new spring plates and u-bolts for the rear (they might be included with the axle). I had a 4 inch lift block so I had to get new rear u-bolts. I needed a conversion u-joint (available at NAPA). I broke a brake line and needed to replace the brake line. The shock and spring mounts are the same (from 1/2 to 3/4 ton). I believe all 8-bolt pick-up truck wheels use the same bolt pattern. I used 16" wheels with a 4.25" or 4.5" offset. A 15" wheel will not clear the front brakes unless you grind the brake caliber. The front was a direct bolt in (steering arm, spring plates, u-joint, shock mounts, spring plates) except the larger brake issue.
I made the same decision. Rather than re-gear I switched to 3/4 tons with 4.10s. I added rear discs ($200), new bearings ($40), new u-joint ($15), new brake line ($??), and it was ready to roll. The new wheels and tires did break the bank, but I guess I could have avoided those.