I got this at auction a few days ago, an IBM Electric Master in quite bad shape. It included a dust covered maintenance sheet, the first entry looks like 30 July 1956, all the way up to at least 23 Jan 1964. Each entry shows the level of time variation at that time - pretty cool. A schematic diagram was also included. I don't have the key to the case so will have to unscrew the back wall of the case to see what condition the movement is in. I'll post that pic once I have done that. That's all I know so far. Plan is to restore and have it running again.