I just finished helping Mark put together a site for his 4.10 gears. I got to see them firsthand and I have to say that the build quality is outstanding.
We made it as clean and simple as possible. Everyone who has been waiting for these can order them right now from the website. Its possible that things may come up that should be added to the site, and we will. :-) I think we are all a little excited about this product, to my knowledge, there have never been aftermarket gears for the Z. I can't wait to try this in my car.
If you have any question about these, feel free to ask in this thread or email Mark directly. Although he is probably reading this thread today so if you ask a question here I'm sure you will see a response from him.