Does anybody know what happened to this mod? A couple of months ago I committed to buying the ring & pinion at the pre-production price. They said it would be available in March. Now I follow-up with the company by e-mail to see if they have a delivery date, and they ignore my messages. I think it is a great mod and will significantly improve acceleration (although it reduces your theoretical top speed, but so what, I don't think I'll ever go 180 mph in my Z).