Need to know what kind of hubs I can use?

He just said he had 10" drums. The picture shows a front drum. I'm almost 100% certain they came that way.

No sir. All drum/drum A-bodies were SBP, 9” drums, 10” drums, all of them until front drums went away with the federal mandate. There were no BBP drum/drum A-bodies.

Here's the TSB on the 73+ drums. They're redesigned B body units, have the larger wheel bearings and large upper ball joint. But if you see point #1, they were redesigned from the B units to be 5x4". You can see the full version at hamtramck historical if you can't read the smaller version below

https://www.hamtramck-historical.com/images/TSBs/1973/05-03-73C page1.jpg

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