Info on 7.25 to 8.75 backing plate swap

Matt that might be just the thing that im looking for. This site is great I am glad that I was turned on to this spot. I am at this point wanting to stay with the sbp. I have a complete disc set up off a 67 formula S and am going with ralley wheels. Matt if you want to get together I think that swap would be great. Also need 8.75 shock mounts if anyone might have them. Thanks a lot Tom