I am detailing under the hood of my 68 Falcon. I would like to remove the main wire harness. Where it goes through the fire wall all the wires go through a square box flush mounted to the firewall. On the other side is the fuse box under the dash. Is this square box a plug that can be pulled appart? I gently pryed on it with a screwdriver, but was afraid to damage something. If I knew it was a plug for sure I would go at it more agressively. I hope someone has been down this road before. Thanks Bill.
Usually tjhey are a junction box from the passenger compartment to the engine compartment. They usually can be pried apart, but are fairly tight and most have ascrew or small bolt in the centre to keep them sealed and from coming apart. They also have a caulking to help seal around the firewall to prevent moisture coming in or corroding the connections. They also may have plastic tabs that lock them together.
Check around it and go slow so you do not do a lot of damage,You then may not be able reconnect properly.