awesome, thanks for your help man, i actually just found out that my cousin has a dana 35 from his explorer and i might just grab that and put it in for now... how has your dana 35 preformed on trail? i never really liked my 28, i always worried that it would break, then it did snap about 3 days ago...
I've been all over California's Sierra Mtns. and then some with my BII. The D35 (TTB) has always done fine for me (take a look at the wheeling pics on my
Cardomain page).
You'll probably want to do a few things to bring the suspension up to today's performance standards though, which may require some research of your own since most of the suspension industry is still stuck woefully back in the '80s when it comes to TTB stuff.
Things I've done are Jeep Cherokee coils, extended radius arms, extended shock mounts w/longer shocks, and a custom K-link steering setup. I also put a "center" limiting cable over the frame which keeps the suspension from unloading as much on steep climbs. A cool side benefit comes when it tightens against the cable, it'll actually mimic a straight axle (forcing more articulation).
As for the mustang axles, I seem to recall they were too wide (and are 28 spline anyway, so there would be no upgrade over your 7.5" as far as the shafts go).
The axle you want is the 31 spline 8.8" from a '91-'01 Explorer. If you get a '95-'01 unit, you'll get disc brakes on it at the same time.