Whos running over 700whp on an 8.75?

So I have the 60, but all I'm using is the housing. I'm upgrading to a 35 spline suregrip posi along with the new 35 spine shafts/green bearings from Dr. Diff. So it certainly wont be stock. I'll be $1600 in it with all the parts. Even less if the 60 I have is 4.10. I gotta crack it open, because if it is then I can use those gears again.
Certainly not a bad plan. And it should hold up well. I just think you’re beyond that at this point. On our race truck we run a full fab 9” housing with 4” tubes with a strange 9+ center section with a spool and 40 spline axles. We are at 650hp and 5300lbs on a 37” tire. We replace gears after every race. We broke a lot of rear ends to get the point of only doing gear changes and would have saved a lot of money had we started with big boy ****.