The diamonds represent junctions - usually splices. Sometimes we'll find the junctions done at terminal instead - probably because production found it easier.
Older diagrams will show welded junctions as solid circles, and connectors as open circles.
So that is supposed to be a welded juntion - and it looks like that drawing is the instrument panel harness.
I think the artist labeled the segments backward from how they work. Seen this in a couple years.
See if on your diagram J2B - 12DBL is coming from the ignition switch.
Yes. I follow you. G = Gages.
I see why you think that. I remember that drawing being a little hard follow.
The G5 wire is connected to the "12 V" tracings on the circuit board (dashed lines)
Ground refers to the ground of the Instrument Voltage Limiter. The IVR has system power available at the bottom connection, ground on the left connection, and "5 V" output on the right connection to the board.
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