As I mentioned, I'll be replacing with new packs but want to do it myself, so I'm gonna start reading up on doing it safely. I have new set of shackles on it now, since I replaced my frame rails a few months ago, so I'm only going to hafta buy the packs now anyway. Wow this thread exploded! Great info...
I would say the only additional cost to the leafs (on the budget) is shackle bushings. Go ahead and get new ones since the old ones are coming out and are likely ready to be replaced anyway. Depending on the condition of the "U" bolts you may need some of those also..