Sorry to Hijack this post, but I had a similar question a few days ago. I swapped a 66/67 b body rear in place of the 8-1/4. I used the 8-1/4 brakes, backing plates on the 8-3/4, but re used the 8-1/4 rear drums. The shoes are the same width, so can I use the new b body drums I have in place of the older 8-1/4 drums I'm currently using? If your quote is correct then I should be good to go. The way I see it as long is there is no interference and the drums are both 10 inch, I should be ok. Thoughts anyone ?