looking for a half- frame option for my LPL 4500, and keep seeing Omega C760 carriers on eBay but none of the descriptions list dimensions of the carrier itself. Wondering if anyone could measure a C760 carrier for me? I’m looking for the outer dimensions and the dimensions of the circular ring on the bottom that would fit into the gate of the negative stage. Also curious if that bottom ring is attached with screws? Appreciate the help!