I have a 1964 Ford 4000. I went to start it the other day and the starter just spun, would not engage the flywheel. After numerous attempts with the same results, I decided to pull the starter. What I found was the end retainer ring on the drive was missing. Not sure how that would even happen, but that's what I have. I looked as best I could for it in the engine but could not see anything. I got a magnetic pick up tool and fished around all I could but no luck. I can easily get a new starter drive, but I'm afraid of where the old retainer went. Would it get into anything and cause damage? Any ideas on finding it without braking the tractor apart? Do you think it would be ok to just be left in there?