Classic/Antique Car Repair: Speedo cable problem, rear axle ratio, speedometer cable

Question
I cleaned up my 1950 Packard standard eight (2392) gearbox over the weekend. 3 speed on the tree. Decided to also clean the speedo cable. Relubricated with graphite powder and it works smoothly. The speedo didnt work previously and it now seems that it is too short to reach inside the gearbox. I cannot feel anything inside the box that it should be engaging. Can feel the worm gear. Do you think i am missing something like a square hole that the square part of the speedo cable should fit to? Hope I explained good enough! The car is still in great condition and the parts are surprisingly wear free although covered in hard grease and dirt. By the way this car is a right hand drive model that was imported here to South Africa.

Answer
If you can feel or see the worm gear (the part that turns on the rear output shaft of the transmission) and there is no mating plastic pinion gear with the square hole in it to receive the speedometer cable, you are indeed missing that pinion.   Is it possible that it dropped off somewhere, or was stored in the car for some reason?

There are different part numbers depending on which rear axle ratio was specified when the car was built - you can't put just any pinion you find in there - you must know your axle ratio and get the right one.  If you have a parts book, you can look up the number, or if you do not have one, measure your rear axle ratio and tell me the result, I can look up the part number for you.

Dick