Step 1: Make mounts for the pucks.
Step 2: I used zip ties to mount each puck to the wire shelf I've recycled - anything wire-ish would work though.
Step 3: Terminate the power cords - I did this twice for convenience!
Step 4: Routing and trimming/neatening the power cords -
Step 5: And done - switch installed, all tested, cords trimmed, neatly managed and working.
Nice to have the task lighting for this new-to-me workbench!