7 1/4 to 8 3/4 swap question?

Swapping to 8 3/4 in my 69 Dart, current set up is 9in drums, My question is can I change out the rears w/o disconnecting the brakes, I really don't want to get into the brakes yet. Can I just remove the 7 1/4 axles pull them, leave the brake hard ware on the backing plate, drill the bottom hole in the 9in backing plate and then assy to the 8 3/4. I know the other 4 bolts line up on the axles, so in thought it should work.

Thanks
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