The 8.5 is stronger than an 8.2 but not a direct swap, obviously. I think either one would handle that power on the street if it never dead-hooks and no side-stepping the clutch.
I built an 8.2 with 3.73s and an Auburn and it worked great with 350ish HP. I wished I had never bothered later, though because I couldn't hardly give it away when I decided to step up the power. I lost a ton of money that could've gone toward the 12 bolt that replaced it.
Just know going in that you won't get that money back if you try to sell later.
69 Malibu Stock 307, Reverse Manual TH350, 4,500 Stall Edge Converter, 4.56 Spool 35 Spline 12 Bolt
76 C20 VortecPro 496 628HP 655 lb/ft TH400 Edge Converter, 4.10 14 bolt