I've been told - and this might only apply to the newer trucks - that a 32" tire will not fit unless you do some major fender trimming. Like almost through the floor panel and firewall. This is where fiberglass fenders would come in really handy for you.
As far as alignment goes, if you can get some beefier parts for the truck, like Moog (or better) heavy duty balljoints, tie rod ends and steering components, find some way to beef up the idler arm, etc., then it should be easier to KEEP an alignment. It won't take much on just about ANY vehicle to lose a good alignment with big tires and having the torsions cranked up... Alignments on big tires for ANY truck will be difficult to dial in. You will need an "old salt" mechanic with the saavy and patience to get it right!
You want coil-overs? The problem will be with getting them on the truck with the stub axles in place. Got $$$$$$ and a really good fabricator? The wallet, er sky's the limit! Coil over will be easier to implement with a solid axle.
I think either direction you take would be really cool. Personally, with as much trouble as you've gone through already to trick our your truck, to get the tire size you want and to utilize the power you have with that 283, I would venture into getting a solid axle. You might want to look around here and check the posts for solid axle conversions; there are quite a few threads on this board alone already.
If you're going all out you might want to look at getting a beefier real axle as well. Might save you some headaches in the long run if you play hard with those big tires. That size tire will more quickly wear out your pinion gears!