The GI circuits is fairly simple. Approx. 7vac from transformer to the light sockets and then to ground. I don’t remember there being anything that switched the GI on and off other than the main power to the transformer. Therefore, if you are actually getting 6.8vac at your GI sockets, measuring from socket to ground… then the problem is between the socket and the ground. Check j1 GI return pins 1 &2… make sure those are actually grounded. Then check that there is continuity from the sockets to this pins…. Somewhere you have the GI return disconnected from ground. My 2 cents.

Glad you found the problem with the ground trace for pins 1&2. Pins 7 & 8 are two separate circuits, you don’t want those to come together… if they do you will blow something. Pin 7 is 5vdc, pin 8 is 7vac. So, no, you definitely don’t want continuity across those two pins.