If you contact Gear Vendor, they will send you an owners manual, and actually talk to you about anything you need. Good customer service.

It is a GM speedo gear. and they will help you determine which one you need.

Too many cars, too many parts, too little coin, too little space to work in, too little time left to make it all happen! Update: down to one ride, still too many parts, a little more jingle in the pocket, gaining space, and it's going to happen this year!