Wow, I'm behind a couple of years. Since I got the Z06 I haven't really kept up on the F-body crowd.
What software are you running?
I know EFIlive has the ability to run a seperate tune (like a valet mode, nitrous tune, etc.) off of a switch that is somehow tied into pin # 56(?) on the PCM. I'm assuming that's how you're running a dry shot in SD mode?
switch position #1 - N/A mode, normal tuning/fueling
switch position #2 - Nitrous mode, tune relatively rich from your nitrous engagement point, onward.
Or, are you just uploading a seperate tune everytime you spray?
Really just curious as to how you're doing it, and I'm thinking (typing?) out loud as to how I'd go about doing it (SD/dry shot).
Whatever it is, good luck with it. Sounds like more of a challenge than I'd ever care to take on.