question on the main harness plug on firewall
raise top of latch with screwdriver and lean top back on plug, then use your screwdriver on bottom of plug and press down on latch while pulling
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Pull back firmly but gently. Take your time in pulling them off. A little up and down motion as you pull.
A little too much force on the plastic retaining tabs and they can snap.
While each of the three connectors is unique and connot be confused, the wires can be mixed up.
Print or draw a copy of the wiring diagram from the '68 FSM, and then verify the positions before removing.
Remove the male terminals from the female connector by squeezing the open diagonal slot in the terminal and push back.
If the foam seal is deteriorated, remove that and replace with new. They can be purchased from Detroit Muscle Technology.
Before reinstalling the male terminals, gently open the slot so the barb will catch in the connector. This is very important or the terminal will back out.
Remove the female terminals by depressing the retaining tab with a release tool. You can buy a tool or make one.
These are original female bulkhead terminals, in this case not Packard 56, but something like a Packard 58.