Two years ago I completed my '65 Sport Fury convertible, a 383 with a floor shift 727. TorqueFlites from 1962-65 had pinions available with teeth from 15 to 21 mounted on the end of the cable.
My car had 2.76 gears and a 17 tooth pinion, but I installed a Suregrip with 3.23 gears, and 205-70-14 radials.
I tried a 21 tooth pinion but the odometer and speedometer read about 17% over actual distance, then I installed the original 17 and a 16 pinion that tried, but both were at least 10% or higher readings. There has to be number of teeth that would fall close to actual distance.

Is there a chart that would work for TFs for those 4 years, using today's radials and gear ratios to go with the limited number if teeth available.

Thanks,