68-70 Dodge A100 3speed manual speedo info needed

That is the for-runner to the A230. I think it was called an A745, and comes with an unsynchronized first gear.

The later models use a smaller diameter speed-o gear, and they are tuneable. Just pop it out and count the teeth, then adjust by using percentages A faster spin requirement requires fewer teeth. the difference is 2.94/3.55-.828. If you find a 30tooth speedo in there, then you would need 30 x .828= 24.8, rounds to 25teeth.