You only need the billet stuff if you’re running in the bottom 10s or faster. Trans in my gn is a stock rebuild with better clutches and a restalled stock converter. Vince did it in 02, and 20k miles later with 100s of 11 second passes, it still performs flawless.
For an ultra wiz bang rebuild, Vince Janis is my go to, he did my T-350 trans. For a standard rebuild, most transmission shops can handle it. Bruce transmission did my GN trans. Demko transmission did a 2004-R for my Dads '90 Estate wagon years ago
I didn't mean to derail this thread lol - just was throwing names out that are the premier GN tranny builders to see if I could guess them. I'm pretty sure most shops can handle a stock rebuild without to much worry but if you're tryin' to eek out a little performance and longevity you do get what you pay for and these guys have a reputation f0r being the "best".
No issues -- good for me to know who does what, and might help out others on the board too. But that doesn't mean your not flexing, ya big show-off.
