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Note that there are only 5 wires associated with the AC system that transit the firewall.
Three go to the blower resistor assembly and one each to the blower relay & pressure control switch (the other side of the control switch runs over to the compressor clutch).
In the engine compartment things get a bit more involved. Your best bet might be to go to the junkyard and surgically remove a combined electrical/vacuum tubing harness. To pull one takes only about an hour - even if you've never done it before. The vacuum supply tube and electrical harness share a common rubber grommet.
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First disconnect all the harness leads (the 5 noted above) and the vacuum tube from the carburetor/manifold. Then - using a screwdriver and some WD-40 - pop the common grommet back
into the cab. With the grommet out of the hole in the FW, all the factory wires/connectors can also be withdrawn into the cab.
Then, when the complete harness is safely on the cab floor, pull the two connectors off the control panel (also the brown power supply from the fuse block). All that remains is to strip the electrical tape where necessary and remove the harness from it's hangers under the dash.
Oh and get all the engine side stuff too - that's only like 3 wires - everything else will have come into the cab with the harness.