Replacing with an Eaton, please advise

Yep :(

I took it back to Larry Puckett today for them to drive it. The guy agrees that it is whining. He says that, since they just replaced the bearings and the R&P, then it must be the "carrier". He showed me one, and there are some MORE gears inside this thing. I am ignorant when it comes to rear differentials, so I really don't know WTF it is. He showed me the GM price for JUST that part.........$1800 WTF!!! I found this one for under $500 w/ one year warranty. I figure that IF my warranty would pay for this, ($200 deductable) I would still just have a stock differential (more problems again probably) and have to go through the whole ordeal that I did last time. SO, I want to know if it is really that hard to replace this thing. I have access to the base lifts, and all tools. I know all I gotta do is pull the axels out a little bit, remove this carrier, transfer the ring gear, and re-install. Anyone have experience with this? What do you guys think?

This is the one I will get.

Eaton Rear (http://store.summitracing.com/partdetail.asp?part=ETN%2D19599%2D010&N=120+400133+304042)

Thanks

If you have gear whine, then probably the pinion depth or the backlash were not set properly.
After setting the depth and backlash, the contact pattern has to be checked.
You could also have a set of loud gears.
If you change the carrier and leave the same pinion depth and backlash you will probably continue to experience gear whine.
I dont think the carrier is causing the gear whine.