Not really sure what this should be called...
It's a 2-piece adapter to turn a 3.5" drive bay into an externally accessible slot for a 2.5" SSD.
Uses SATA extension p/n 29652A (EAN/UPC code 4043718180448) for the connector.
2 M3 screws attach the extension cable. 2 M3 nuts in slots allow for adjustment to line up the front panel. 2 sizes of slot part available to help with that. I needed the longer one.
To install, M3 screws work. I'm sure a close imperial size would be fine also.
There are holes at 6 mm as well as 6.35 mm from the bottom to allow for some wiggle room.
I'm still trying to think of an elegant way to make an eject mechanism, but for now I'm making do with a piece of tape to pull on.