[jonmc56]

Thanks man, appreciate the info. I double checked that I have 11x2 brakes in the rear, so that should be good.

The 'width of rear ends' question is funny, I spent a ton of time searching here. The question has been asked dozens of times, and the answers are mostly incomplete. Here are my notes on the best info I was able to find:

Rear end width apparently changed mid year in 1970.

67-69 (and some 1970 models) 6-lug is 55.5" wide - from backing plate to backing plate. 30.5 long axles.

71-72 (and some 6-lug 1970 models) 5-lug is 57" wide - from backing plate to backing plate. 31 5/16 long axles.

Square-body: The width of a stock 10 bolt rear end in a '84 C10 will be 63.5" WMS to WMS (Wheel Mounting Surface) - obviously this is not the same measurement as above.

So.... I think my rear end is a little more narrow than the one in your truck, which may be a good thing, I think my truck is a couple of inches lower in the rear also, a little worried about rubbing the outer fender with the same size wheels/tires.

Anyway, appreciate your help. Glad the pinion issue seems resolved.