Dh, did you go through your axles before you put them in? If so, can you recommend a good bearing and seal kit for them? I have an auto zone about 100 yards "as the crow flies" from me but they seem very incompetent. My latest stop there the one dude didn't know what PB Blaster was... We have Oreilly's, Napa, Carquest. Anyone have an opinion?
Mine is a long story. I didn't go through the front, but reused my outers, where most of the crucial parts are. In your case, swapping from 6 lug to 8 lug, you'll need to use the new outers. For a truck that will be driven on the street, i'd replace all outer related stuff. Hub/Rotor, caliper, brake pads, bearings, seals, ball joints. It'll cost you, but might as well do it when its on the ground, rather than when you need to drive the truck.
Didn't go through the rear, and ended up paying to get it re-setup up when the pinion seal had to be replaced. That $800 killed any savings by swapping axles. I DID go through all the 14ff brakes though, and replaced wheel cylinders as cheap insurance. If the shoes have decent life, leave them. Just take the brakes apart and clean it all up and lube it all. 14FF brake shoes are essentially 100,000 mile shoes, so if they are half life remaining....no need to swap.
Also, be aware that the older backing plates for the e brakes are a different style than your 91 ebrakes. I found a newer style (late 80's) 14ff to solve this problem, as i didn't want to mess with the backing plate swap, as there are many variations.
In terms of parts houses, stay away from autozone and oreilly's like the plague. Autozone is the WORST< but oreilly's has been giving them some great competition for that title since the switch over from kragen. You'll pay at napa, but its worth it in quality. Truthfully, i'd find what you want, and order it all somewhere online. I'd check rockauto first, and see if you can get the brands you want.
Good luck!