Please tell me what parts interchange between the 2.45/2.25 vice 2.71->up 8 1/4 axle

What are you talkin about? Where I said 2.71? Are you gonna run a 2.71? No. Do like we recommended and get the carrier that'll take a 3.55 and you'll have the right one.
No nevermind man has nothing to do with what you said in this post