Hawkrod
I agree with your call on 2 different calipers. I have my dad"s 73 f250 and when picked up new pads I found out there were 3 different gvw ratings for that year and we had the 8600 gvw version and the pads were much bigger and beefier than the single piston and much more expensive. I just swapped a 79 f150 6900 gvw susension complete front end in a 66 w/no problem even though the new one is wider than the 66. I be leary of redrilling the axle holes. FWIW
OldTrapper