your in NC, so your rust should be too bad.
Get some really good wood wedges. use them inbetween your frame and rail when your replacing the pucks- just in case the jack or whatever your using to lift the body comes loose.
WD 40 doesnt really help too much, cause you cant reach most of the bolt threads. But you can use it where it can reach.
Use a proper fitting socket. (like from an impact set) that grips to the whole side. You might need all the grip you can get. Extensions are a big help. nothing like trying to reach 3 feet up to remove a bolt.. /forums/images/graemlins/rotfl.gif
and if you figure out a good way to remove the two in the back, you let me know!