need recommendations...switching to bbp axles

What is the best way to switch from my existing rear 10" drums (1.75") sbp on my 67 barracuda with 8 3/4, to big bolt pattern.

Drums and shoes and hardware on rear all needs replacing anyways so the question is what is the best option for backing plates and drums as I plan on buying a new set of axles from Dr.Diff.
Do I need to aquire backing plates used?
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