I use 4 captive nuts in the bench top and have the presses mounted on 12"X12" 3/4" plywood plates. Time to change presses out just 4 bolts to remove. swap the press and bolt another press down. Guess it is strong enough it works for the 50BMG press and you know there is some pressure applied when sizing those and popping out the crimped in primer (add a cheater bar on the press handle to make it easier on me).
The presses are mounted to the plates with 1/4 inch flat head screws from the bottom counter sunk so there is a flat surface to mate to the bench.
The presses are mounted to the plates with 1/4 inch flat head screws from the bottom counter sunk so there is a flat surface to mate to the bench.