When replacing my pump, I pulled the four bolts to the seal completely. I know, I know..... Grrrrr!!!! The bottom half fell down into well.

If the bottom half is a full ring, then, the PVC pipe should be holding it, and I can pull the pipe and retrieve it.

If it is not a full ring, I wonder if it is lodged at the top of the pump and against the casing (maybe so I can lower a magnet tied to a rope and fish it out).

Does anyone know the shape of the bottom half into which the bolts thread?