I haven't used this stuff but I have used amsoil gl-4 Manual Transmission & Transaxle Gear Lube 75W-90 and it was amazing. The butter smooth feel of the trans was a surprise. My friend tried to use stuff off the shelf that said it was compatible but it didn't shift or feel smooth until he bought this amsoil gl-4. It's expensive but once you feel it you won't regret spending the money.
https://www.amsoil.com/shop/by-produ...=213&zo=510227

 

Go with amsoil. My Napa actually carried it, from what I've read even for other cars this seems to be the best gl4 on the market

 

I did some reading back in the day and redline was popular but I read it wasn't as smooth especially when it was cold. Amsoil gl-4 feels really smooth and we put it in two old cars that are daily drivers.