[quote=iwantacobra427;828729]Do you guys think I made a mistake with this setup: TKO 600, 0.64 OD, 3.77 rear end QUOTE]
I think you'll love this set up. 2.41 final drive is pretty good for cruising. it's the guys that go nuts that get into hot water, with a final drive around 2.0! All a gear that tall will do is bog the engine unless you're running at Daytona. I always like my final drive to be in the 2.50-2.70 range and you're RPM will hover close to the beginning of the power ramp of the cam at cruising speed most of the time. That is the ticket....probably more than one, too....
Just monkey with the REAR gears until they suit your trans. A lot easier to find differential gears than get Tremec to make a trans for you!