So while I was relaxing under the a100, back wheels up on old solid steel ramps, after dealing with the park pawl & Neutral Switch circuit fix; I decided to pull & examine the speedometer angle drive gear.
Cleaning all the grime was time consuming but of course did6want any of the 2t+ year Kansas farm mud to get in the tailcone housing while removing the gear unit.
1st ? was 'status of the plastic gear sets ( shaft drive gear & angle drive gear) &
2nd: was the speedometer cable end still a square one.
Well, blessed again, both plastic gears were just fine.
So brake cleaner-ed up the drive unit & then wire wheeled the housing to 'make like New.
Gotta luv 56 year old MADE IN AMERICA components that still function like brand new.
The cable however was not properly fitted into the gear so reason 1 why 'no speedometer'.