Classic/Antique Car Repair: Rear end ratio for 51 ford, rear axle ratio, ford tudor

Question
Looking for a driven gear # for my 51 ford tudor sedan with
a flat head V8, would like to know what the factory rear end
ratio was. It is a 3 speed manual (no overdrive)
Thank you (reason, have a broken speedometer cable and thought I would replace the driven gear also.

Answer
According to my parts book, all without overdrive except the station wagon had the same rear axle ratio, but that ratio is not given in the book.  My guess is that it is a 3.54, but you could jack up one rear wheel and spin the driveshaft one complete turn while you count the turns of the wheel - it will turn just over 7 times for one turn of the driveshaft if it is a 3.54.   (7.08 turns to be exact).

The speedometer cable drive gear is shown as part number 8L-17322B.

Dick