10"x 1.75' brake drum BBP???

Same backing plates.
upload_2020-3-31_16-35-43.png

I have no idea what the project is.
Agree that if the axle flanges are further out, then the 10 x 1.75 unlikely to work out.

Probably the easiest to work from the most difficult to change, the axles shafts, and figure out what drums would fit best.