I've been playing around with Josh's tune for a few weeks now, and it gets a little faster every week. Down to 13.0 @103 now, bet she's got 12.9's easy.
Couple of things to check:
Have you logged rail pressure? Did it maintain?
Do you have the same OS as Josh, or did you manually have to convert it?
I popped the high MAP code, but I think we've got that solved, we'll find out tonight.
95MPH is good MPH for a 14.6, are you hooking up when you launch? Gaining 0.4 in a night is huge, the variability might be in coming off the line.
315's might be holding you back a 0.1 or two.
Post your fuel logs and I'll try to help with some of the tweaks I had to use tailor it to my truck.
It is a pretty sweet race tune. Easily in to the low to mid 13's with your combo.