I've just realised the mains voltage selector is the same make and design
just different markings.
That too is unreliable I now find concentrating on it, so now permanently
wired for 240V , no bad thing, in case someone mistakes this selector for
changing oputput for different cabs and in the UK.

At least 1970s and earlier loop-thru-tag and solder assembly has gone by the
board by 2005