How much hp/torq will an OEM 833 4sp and 8 3/4 take?

Will be fine until you put sticky tires on it. Traction kills parts. I'm not sure what your build will consist of but sub 600hp should be fine. The rear will go before trans. Then clutch and the trans if you make enough power. A slipper clutch would cure this but more of a race setup. I'd talk to liberty