If you already have a used torsen, my advice would be to used Quick Performance axles and bearing package with either 3.23s or 3.73s depending on what you use the car for. My donor axle had 3.23s so I used those. If all I had was 2.73s, I probably would have bought 3.73s.
G-bodies are still relatively new to me but I've been playing with F-bodies forever. I broke 3 stock ten bolts. One clutch type and two torsens. All on street tires behind a T56. I ran stock 28 spline axles, 4.10 gears, and a housing brace with all three. Never broke an axle, never broke the gears. The 7.5 should have a much easier life behind an automatic unless you use a transbrake. There are guys running 10s reliably with a stock unopened 7.5 behind an auto.