Car won't crank, Guage lights flash, and how do I pull my starter?

FWIW. On 67 and probably your 66, the parking light fuse has two wires out. One to the dome light, the other to the B2 terminal on the headlight switch. Crimped onto the B2 connector is the wire to the brake light switch.
Actually, same concept but the routing to the instrument lamps at least for '67 is as follows.
Power comes from the main splice.
It goes to the Fuse shared with the brake lights.
Fuse out to the headlight switch B2 terminal, through the resistor controlled by the knob, then out the Instrument lamp terminal.
Tan wire from intr. terminal feeds a 3 amp fuse in the fusebox.
Then from the 3 amp fuse to a splice and connector(s) to the lamps.
Some or all lamps final connection is through the printed circuit board.
@RedFish will prob know if the 66 Barracuda instrument lamps are on the cicuit board.
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