So the saga continued today.

For those speaking about checking the cables for corrosion. How did you determine there was corrosion in the middle of a cable without remove the insulation? Assuming multimeter on each end to measure resistance.

Removed the bendix gear, cleaned, and lubricated with white lithium grease. When the engine is cranked, the bendix gear raises as it should, turns the main fly wheel very shortly (Maybe 2 seconds). Then bendix and flywheel both stop with the bendix staying raised. Once the key is turned off the bendix drops.

I can turn the flywheel by hand even with plugs in. With plugs removed there is a cycle of fairly easy spin and then it's hard to turn like the plugs are in.

Pictures of starter internals.