Switch and Lamptester for 'the bench'
Designed for Williams System11 but, with some rewiring, can be used for SYS3..7 also.
Add jumpers to the switchtesters on switches you want to have permanently closed.
Add 8 resistors of 2,2K .. 4,7K depending on how 'intense' you want the LEDs.
both testers 'in action' on WillFA11 (emulated game: Highspeed)
documentation
For System11 you can use Molex 1:1 connectors e.g. from Aliexpress here
For System7 you need to change some wires, see tables below. Pins marked green can be left 'in place', pins marked orange need to be changed.