Tractor is back in action but it still took a magic dance

Picked up the starter and alternator, cleaned them up, reinstalled them, turned the key, no start.

I thought for sure the problem was that the starter was just feeling neglected and needed a good cleaning but all the scraping and brushing went unacknowledged. When I turn the key I can hear the solenoid engaging but no crank. When I arc the starter posts with a screwdriver, it spins up but solenoid doesn't engage. I think, giving it a little spin with the screw driver before trying to turn the key again got the starter in the right mood. I was able to jiggle the key just right and brought the tractor to life. I think the folks at the repair shop were subject to the voodoo of the starer because they said it appeared to be in good condition. The batteries and alternator seem to be working properly.