You should be able to just pull the axles on both truck and the replacement rear end, and then just swap the differential housing/torque tube in. Some new gaskets and you're good to go. No need to mess with brakes.
Swapping the differential/torque tube isn't all that hard and there's no need to mess with gear pattern setup or anything else. I would say that it's easier than swapping brakes over, as you'd have to pull axles to do that anyway.


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.