Custom armboard setup on my Victor CL2P plinth machined out of 3/4" (19mm) aluminum bar stock. Inserts for arms machined from 1/4" aluminum plate and painted red. Arms may be quickly removed by removing (6) 10-32 screws and unplugging DIN connector.
Custom built Victor (JVC) turntable, Audio Research SP8 ver5 preamp, MC40 monoblock amps and HeathKit AS101 speakers (Altec Valencias in much nicer cabinets)