The actual title I need this for is OXO, but I would imagine that all the '70s Williams EMs have the same stock.
Specifically it is the inside-door anti-slam switch; it has a blade with a large mass, another blade that is bent, and there is a big fish-paper thing that isolates it from the coin door. I think I know the layup, but I have some extra pieces that makes me unsure. I'm even unsure as to the screws that attach it.
Thanks to all in advance!