Gentlemen, your absolutely correct about tire size & gearing affecting the stock speedometer. However, we are completing a ground up resto-mod build that has all modern dakota digital gauges & monitors. There is NO cable in the new system. The dakota digital converter mounts directly to the stock speedometer and is calibrated using your existing tires & gears. The computer does all the work for you. I just need a factory speedometer drive unit to plug into our rebuilt trani. Can you help me out?
Try checking with your local chevy dealer. They should be able to look up p/n's for the gears that came with you car/trans.
The gears them selves are easy to get once you know which ones you need. Should we assume that the drive gear is already installed in the trans.
Is it possible you need what is called the bullet assy? That should be the piece that holds the driven gear into the trans and the cable would attach to.
Here is a website that list different gears for the trans.