When I bought this mill it came with an overarm support but no means of holding it to the overarm proper. There was a hole through the support casting at a right angle to the overarm hole, and it was clear from looking at pictures of other peoples mills that there was supposed to be a cotter there to hold it in place. I decided to try and make a cotter to fit, and looked online for information on how to do it. Not much showed up, although I got enough detail to think I could figure it out.
This was a fun one. I saw a listing on craigslist for a small horizontal milling machine. It was about two hours south of Seattle in a little town called Castle Rock. The photos looked pretty cool, and it had a shop made vertical head and a bunch of tooling. I had never used a horizontal mill, but after some very brief research I decided I wanted it. The price seemed reasonable, but what did I know.