Just thinkin.........
There are empty holes on the PCB. IIRC there were 2 different
parts, one a photo-isolator the other a relay. They had different pin outs so some unused holes.
The replacements were the grey 1 inch long, flatish isolator.
I THINK the resistor was OEM, not added.
On the PCB if the transistors are plugged in you may have knocked one
part out & killed the ON /OFF so check that.
So back to the olden days....... All of these chassii were in 25" sets.
I was the jig man so being on the road was rare to me. When there was trouble in this area the road man would order a rebuilt selector assy instead of messing
with multi trips on an often int problem.
Zeno
