Then removed the speedometer from the dash cluster. Simple. 2 screws held it on the steel cluster.
The drive of the speedometer would not turn with a small ( eyeglasses fix set size) screwdriver.
Between PB Blaster , brake cleaner (carefully not to mess up Odometer discs), & Assembly Lube ( thin oil + graphite lube) & Q tips; after about 1/2 hour the speedometer head units & plastic Odometer drivegears worked like New.
Used Hydrogen Peroxide to clean up the speedometer face & the #s on the Odometer discs.
Reinstalled the speedometer in the cluster & the cluster in the dash. Ordered a new correct length speedometer cable & now looking forward to having a working Speedometer.
Also carefully cleaned up the speedometer needle ( after this pic) and will give it a spritz of fluorescent orange.
I did get the alternator gauge working a few years ago. The oil pressure idiot light bulb itself works but the sending unit is an issue. More on that later.