If it's a YS1 GSR trans you may have issues. I believe it's the input shat that's a little different in the GSR YS1. I can't remember off the top of my head though. I'll get back to you on that one.
You'll also need to get a 92-93 clutch kit as the splines are different from 90-91 to 92-93.
You need to find out if it's a USDM GSR YS1, a USDM LS YS1, or a JDM YS1(with or without LSD).