I realize that you have to draw a line in the sand, but I would take exception to the fact that you will finance a truck that is showing 748,579 on the clock, but not 752,689 unless it's been rebuilt. I'm maybe assuming too much here, but a truck with 650k can sh1t the bed just as fast as a truck with 900k, both having original engines. My opinion, I'd much rather spend my money on a '96 through '02, and plan on overhauling the engine in the next few years than take a chance on a 600k truck that more than likely is going to require an overhaul as well in a couple years, plus the added aggravation of emissions troubles and lost time in the shop.
Just an observation.