Re: gauging interest in a dyno day in Livermore
Yes, pretty much all of the programmers store the stock tune internally so you can flash it back to stock if needed. Diablo and SCT both do this.
As for if it is worth while to tune a stock V6, yes, it is. You car is currently tuned for 87, so a new tune will be for 91 in your case (you can also store multiple tunes on an SCT XCal tuner so you can have a tune for multiple grades of gas).
Basically, you will be able to better utilize your car's potential with a tune....even in stock form.
"When I know more, I'll be forthcoming. Or I won't be forthcoming, and I'll be honestly deceptive." - Les Miles