Dirk,
Thanks so much for your input and insight to my C6 issues. I was on my way back home from the airport reading your post and one of the guys I've had running this problem down called me. Long story short, his tranny guy had pretty much the same response as you. If I went with an AOD, I could keep the 3.73 gearing in the rear end and maybe get a great balance.
Going to start checking out some options for an AOD....
PS> I'm getting ready to start a new build of a 34 Ford 3 window. That will be a lot milder than the cobra, so I can always use the C6 in that car
Thanks again!!!