Well hopefully these are all the same as the mids in question are up on a shelf way in the back. Suspect Harman period as have seen some Infinity mids online with what looks like the same backing cup with screws.
Currently have the backing cups tacked down with hot glue, but if can procure the screws to batten down the cups would be great.
So as the header states would like to know size are the screws that pass through the cups into the back of the magnet.
Thanks all