For the Chevy Swap:
Read this 63" Chevy FAQ
Some people swear by the 63" chevy swap, great flex etc, but you are using used springs, no guarantee how much (if any) lift you will get. some say they drag on obstacles (bad departure angle)
For Rears up front:
Read this RUF FAQ
4Crawler's website also has some great info on spring swaps
Link to 4Crawler
getting it all together in one package is nice...I pieced my front kit together after getting a 'great deal' on a set of springs. Ask Brian (waskillywabbit) I had a ton of small orders for mounts etc over the last year or do.
you might consider going lower than 5" springs. My '81 with 5" spring has a high center of gravity. I haven't wheeled it yet (dual cases being installed
) but I have a feeling I may be pulling leafs to lower it.
If you go with either a complete kit from Wab-fab or All-Pro your springs with settle somewhat.