Looking to buy/build 500-600 fwhp 360

Trans is a fresh rebuild, and it is the "Hemi" 4 speed. My dad had it build for drag racing. He has the synchronizers modified, something about every other tooth removed. I think the 3rd member on the 8 3/4 is a posi that has been rebuilt. I figured the trans would hold up if they were behind Hemi's. I guess if it breaks I will have to upgrade to a Lenco and Dana 60. Just kidding, don't really want to do that...
The transmission is fine.. I don't know what he's talking about... Now the 8 3/4...
With a 4 speed and sticky tires... That could be a problem... Ask me how I know...
Also the 200 nitrous shot ain't just throw a bottle in the trunk... $1500-2k done correctly.. ask me how I know...
Advice: build a separate engine or buy the blue print... You should be deep into the 11's with all motor.. ask me how I know.. a couple 2-3k in rear suspension and shocks, a clutch tamer and you should be seeing tens all motor ..
And don't forget your roll bar under 11.5...