The 8 1/4 thread

I don't know what carrier I have but i know its wrong. I'm putting a 3.55 ring gear in. I was hoping someone else did this before. I only need to move it a 1/16 to 1/8 more I will drill a small hole (.050) to see how thick it is. I can turn it between centers,the same way mopar did. I'll pest results if I don't chicken out. I can only loose a sure grip I can't use Thanks for the reply Jim