[Yenko boy]

Hello all I have a 427 BBC and im thinking of putting a large cam in it to reach my goals, cam range will be in the 3000/3500-7500rpm range. I was dead set on using a tko 600 before i decided to go with a larger cam. But after playing with gear claculators and doing alot of research seems to be 2 major problems. 1st problem is looks like im going to have to run steep gears in the rear so that in o/d my revs won't be running to low. Im talking possibly 4.30's maybe a little more, cam this size in a 427 BBC gonna need almost 3000 rpm in o/d gear to be happy. 2nd problem is with gearing this steep 4.30s or more and at my estimated power 600rwhp tko600 gearing seems too short. Dont wanna be roasting tires 1-3. So im just wandering what other transmissions might fit my needs better. And im thinking it has to be others out there who had to tackle same problems so im looking for some advice. Thx...