Driven gear btwn. speed. cable and tranny

I need a new driven gear. However i dunno the gear ratio. Does anyone know the gear ratio with a purple driven gear in a Turbo Hydromatic 350? Thanks

I went out to TCI, the tranny guys and they have a chart that shows all the different colors of gears for speedo gears. It might help you out. Good luck. Heres the link.

http://www.tciauto.com/components/speedometer_gears.htm