You didnt specify what rear you have. I will assume you are talking the factory 8.5 10 bolt.
The Eaton posi is a good street differential. But once you get out of the 10's and launching on a trans brake, you are really into spool territory.
The problem with the Eatons....especially the 33 spline versions is that the registers where the carrier bearings get pressed onto, get thinner since the 33 spline axle is larger than the 28 or 30 spline units. The cases are very soft steel and will fracture there.
Your best bet is a spool.