I've seen the large plug from the playfield to the backbox cause problems with groups of switches. May be worth taking it apart, cleaning, and checking continuity from the playfield side back to the main board connector(s).

All of the switches you named are on the same "column" (#5, Green-Black wire, 1J8-5, Q43). At 35 years old it is certainly a connection, loose wire in a crimp, or cracked solder joint. Been there on a High Speed I'm restoring.

Once located, the fix is a quick one

HS_Matrix (resized).JPG

Definitely double check all of the wiring in the area where the work was done. The diagram calls out the wires for the switches in question.

BTW: The "large connector" is on one of the playfield cables. Large, multi-pin connector maybe 24+ pins.

I can do it. Send me a direct message and we can discuss details.