I don't have a "hook up" per se. I got a helluva deal on some 12 bolt HMMVV beadlocks with PVC inserts (locking inner and outer beads) that have the centers cut out and rewelded with the correct bolt pattern for my axles and more appropriate backspacing than the stock 7" that the HMMVV uses. They also are two tone powder coated and have rock rings welded to the outer rim. They come with the HMMVV Goodyear 37s. The guy who makes them has a contract with the gov to liquidate old stock. I essentially get replacement 37s at under $75 a piece with near perfect tread...I bought 5 to start.

There is a guy in SOCAL, though, who deals in the bigger tires. I'll see if I can dig up a link to his site.

Regarding the coil rear, that may be the way to go. I had a chance to run coilovers back there and am now kind of kicking myself for not doing it...