Wow, there's a shat ton of misinformation goin' on in the past couple days here
FJ40 F&R, FJ60/62 F&R, FJ80 R are all 9.5" diffs. The 80 has the strongest of these, though. I can't remember why, but it's not a HUGE strength difference.
Minitruck front diff is LP 8". FJ80 front diff is HP 8".
If you flip a 9.5" diff to high pinion, I believe you'd need to mount your engine in the rear. Otherwise, you'll be going backwards with a front-mounted engine. It'll spin the axleshafts the wrong way.
If any of this is wrong, please correct. This is just all that I've gathered over the years. Thought I'd try to clear it up in one post
