I’m building a 455 olds and I have a couple of questions. I just bought and installed Oil restrictors from mondello racing, did i need them? I pulled the crank and need to install new main bearings should i take it to a machine shop? I called a machine shop and they said i could do it myself. The old bearings are clevit 77 and they have a 20 on the other side......is that how much the cranks been cut? Any answers would be great thanks "B"