Rear suspension upgrade/refresh questions

I've been going back and forth with Eric from archive garage a little on getting a set of springs (Medium duty) as I don't tow or haul much of anything heavy. He said they'll givee about 2 inches of lift plus a 2"block it should get me back to where I'm at height wise.
The idea is to refresh what are likely original leafs, get rid of 4" block and have a little, if not much better capacity back there. I've read good reviews on these. Trying to round up everything needed. After talking to Eric aside from parts like u-bolt for the flip kit, a 2 inch block (I.need to source this somewhere suggestions welcome) and the springs is there anything else I should have on hand just in case or do while I'm in there?

Will be rebuilding one of my rear icon shocks now that I know they'll work for the set-up. It's leaking like a mofo. Not doing the relocation kit. Or I may buy some Bilsteins or non-resi icons if I can find right length and rebuild later and have spares.
Airbags will probably stay on truck just have to figure them out later don't have separate lines and i.have a slow leak somewhere. Any real need for new bumps at this time?

Thanks for any input!