Switching to the 904 trans is probably worth 1-3 tenths alone. The cam change might be worth a tenth...might run the same....hard to say, if you already have it, try it and see. With more gear the new cam would probably be happy (because you will probably give up some low end torque with the increase in duration). Stock stroke small blocks like a little gear, like the others said, 4.30-4.56 gear sounds good...and a good 8" converter......but now that we suggested rebuilding your whole car, what do you think? Just kidding:D, good luck with the car, and let us know how it goes.