ls1anxiety

I've got a quick question, I just got home from afghanistan a little less than a week ago. I paid a co-worker to give me a ride to louisville to pick up my 01' ws6. As I'm driving it home i realized that the rear end is making more noise than it did a year ago before i deployed, I just figured it was from sitting. Well i finally make it to my neighborhood and I turn around so I can back it in to my garage and as I'm reversing up the driveway my rear end goes out. Needless to say I was pretty pissed. I ended up finding a rear end on craigslist out of a 97 ws6 so I jumped on it. My question is should I swap the internals out of the rear end or swap over the brakes. Any advice would be great I've already waited a year to drive my car i'm tired of waiting lol. What do you guys think I should do?