[dsraven]

just a heads up on lowering the rear suspension, if you weld in a IFS up front that will usually lower the truck. the problem is that the rear can only be lowered a certain amount until the axle will hit the frame. i suggest to leave at least 3 inches above the axle or else take out some good dental insurance. of course a good jounce stop will also be a good idea at that point.
you could check ogre's build as he has pics of the rear suspension with about the 3 inch limit above. there are some pics of the truck from the side as well so you can check out the ride height.
there are bolt in IFS kits as well. that allows the possibility of some rake angle changes if needed
another thing to know is that the front wheel opening in the fender is tapered at the rear but more rounded at the front so as the truck is lowered the wheel tends to look like it is not centred in the opening. most guys move the axle centre line ahead some to compensate for this. it can make a big difference for choosing your tire outside diameter as well. best to have the tire size chosen and some "project" wheels so you can get the look you're after.
best of luck finding a good donor vehicle, it seems like the larger trucks can be in better shape body wise but if they have the big fender front end then some other stuff will also be a little different. ,maybe best to keep with the standard sized front fenders, like a 3/4 ton down. some guys, however, buy a big truck, because they sometimes don't see much driving especially in winter, and then use the good cab on the smaller truck frame and fender set up.