rearend gear

[69ptcamaro]

I have searched this forum and the automatic forum for an answer to my question, but I have yet to find someone else with the same setup as me. I have a 69 Camaro that will have tires right around 26" tall on either 17 or 18" rims. I ordered a 3.42 gear for my 12 bolt because I had planned to put a M21 in the car that I already have. I think I am going to go ahead and have a 4l60E or a 4l80E built instead. That is another question I have for a different forum, but feel free to answer if you feel so inclined. Is the 60E strong enough? The engine is a 468 with factory open chamber rectangle port heads, a decent hydraulic flat tappet cam (around .530 lift), good aluminum intake, flat top forged pistons, and probably a 750 or 850 carb. I have a lot of details to work out on the engine, but I want to make 500 hp. Will that 3.42 gear work ok for me? The car will be for sale when I am finished, but it is a pro-touring type car that might go to the strip once a year. I am much more worried about it being easy to drive than anything else. Thanks for any help.