300hp TR8 Need rear Differential Performance options

[BlackFly]

I have a 300hp Triumph TR8. I upgraded the Springs, Shocks, Brakes, exhaust, Body Kit, Custom Vertical Doors, Custom wheels (4x100), Custom roll cage, custom headlights and fog lights. This Car Runs great, Looks great, but i need more off the line. I did put in a 1989 Toyota Celica W56 5 speed Transmission Kit from Australia.... Now I need to upgrade my rear diff for more beanz off the line. What are my options? 8" Mustang? Quaife LSD ? What is the best gear ratio? 3.70:1 ? 3.90:1?  Has anyone done any of this? What the difference noticeable? Was it worth it?  Thoughts... please