So, I unbolted the tranny extension and discovered no drive gear on the out put shaft. Also the drive gear/ "bullet" was missing from the TH350 as well. Went to my buddy Joey at Westside transmissions in los Banos. For $20 he gave me a 20 tooth driven gear/bullet set up, the 7 tooth drive gear and the little clip to keep the drive gear in place. (Actually he gave me the parts and I insisted he take the $20). I have a 3.73 posi with 27 inch tall tires, that's what the calculator called for (7 tooth drive 20 tooth driven).
While I was at it I discovered once the drive shaft was out that the rear Ujoint was binding, so I went to O'Reily Auto Parts and for $30 I bought 2 U joints and a large C Clamp and my 15 year old son Jimmy and I di the U joints together yesterday...great father son time together....Got a working speedometer now!
Next up will be the radiator/shroud.