WOW what a neat project!!!!! (What can I say, I'm an old farm kid and have always had a soft spot for big trucks )

Don't know if I can be much help on the suspension part, but as far as drivetrains, I may have some suggestions if you don't intend to use the original (I suspect parts may be a little hard to come by for that engine). I've done a couple of big truck projects in the past (52 Ford F6 conventional cab w/402 Chevy BB, offy bellhousing adaptor to original tranny and 2 spd rear,..... 51 Ford F6 Cab Over with a 440 Chrysler, Torqueflight and Hone Overdrive).

Good luck with the project.