I will chime in, as I have done the F,M,J body disc swap on my 70 Sport Satellite . . . no issue with the taller (think it is like 1/8"??) spindle. My car has 10,000 miles on it since doing . . . couple things I ran into . . . needed to put a washer on the bottom original bolts (on the nut side), used rear mount calipers (think from 5th ave), so that bleeder screw was in upper position, and stainless steel brake lines from Dr. Diff . . . no issues at all !!! Think I used the larger rotors with the caliper adapter . . . no tire wear issues - the larger spindle issue is supposedly at FULL extension, where the upper ball joint "might" bind or hit ?? . . . I have never had issue (also used tubular upper control arms from Firm Feel) . . . all is talk until you do it in real world . . . just saying . . . Oh, and yes, have 15x7 road wheels (magnum 500's) . . .

Cheers

Mark