Hi Glenn.
Have you checked any of our forum sponsors?
I did get a tune once for my C6 emailed to me from Chuck Mosello at Corvettes of Westchester a number of years ago, ~ 2009? To be honest, I can't say it was a bumpless install but my C6 was everything they advertised for automatic transmission and engine performance afterwards.
The main question I asked was; "how easy is it to back out of the tune"?
Good luck.