AC-460 That's alot of motor. In stead of the 9" cut down, you might want to look at a quick change rearend kit from Franklin. They use 9" parts and the rearend is good for 750-800HP. You have about 600 differnt gear combos. I saw a ERA with this setup here on the forum. It's doable, and about the same cost as a custom 9" setup. The franklin can have the brakes on either end of the shafts. Changing the gears, about 20 minutes. Cool look under the car priceless
It's also stronger than most other setups and lighter too. Rick L.