I purchased a used starter here as mine was giving the dreaded squeal on cold mornings as it wasn't releasing from the flywheel as it should. I took the starter apart, cleaned and greased it up then installed. Car started up and I drove home. (was at a friends as I don't have a garage)
I didn't go anywhere the next day, but at about 8:30pm I went into my office and stepped on something... It was the spring that goes on the plunger... Was a simple fix, but I fixed it out in the cold in the dark. Thankfully, I replaced the two philips screws with bolts so I could remove the selinoid without removing the starter!