Lowering rear with blocks - ??s

[72c10step]

I've got a 72 Chevy with a coil rear end and I'd like to even out the stance a bit. I've been reading some of the posts on the board, and have a few questions. A lot of people are using thick walled square stock and boxing the ends, then getting longer U-bolts. Is this all that needs to be done? Are there any other concerns, like panhard bar, shocks, bumpstops, etc., that I should worry about? I'd lower it a bit with springs, but I eventually (hopefully in a few years) will go to airbags, so I don't want to waste the money on springs. Thanks for the help, here's my truck right now as it stands. I'd like to get it almost even or just a slight rake, only maybe a 1-2" drop in the rear.