Hi, Before you assume that your power pack is not working.. The white wire coming off the power pack is the hi voltage line that powers
ALL the electroluminescent ( EL) items. Gauges, shifter indicator and radio face. In a 67, the original clock would not have EL lighting, however the wire for it may be in the harness to the console. If there is a short to ground in any of the EL items, or wiring, it will cause the power pack to shut down and not produce the hi volts to make the EL work. Also, the DC power input to the power pack is fed from the variable dimmer control on the headlight switch, so that could be defective. The + 12 volts to the power pack is on the orange wire at the connector, the chassis of the pack
must have a good ground connection.
If you want to test it in the car, get the
white wire disconnected at the power pack connector, and turn lights on, dimmer to full bright, if power pack is good, you should hear a faint hi frequency whine from the power pack. If so, it's probably OK.
Or...remove the power pack and apply +12 VDC to the orange wire, - 12VDC to the chassis of the power pack. You should hear the whine. Using a multi meter, measure the output of the terminal of the
white wire coming from the power pack and chassis of power pack. Should be somewhere about 200-250
Volts AC. If power pack works, you probably have a short in one of the EL items. For gauge and power pack issues contact Mark,
https://thegaugedoc.com/
Good luck with it.. Terry