When doing an engine swap or relocating the 500 harness, you will need to open and remove the glue filled pass through connector so you can easily remove/add wires to your harness.
The glue that was used to seal the space between the wires and this connector (or grommet) is very tough and difficult to work with. Boiling hot water will soften it to the point removal is quite easy (and not sticky). For the engine side harness, I normally take the entire harness into the house and use the kitchen stove (yes, the wife "loves it" when I do this) for ready access to the boiling water.
BOILING WATER is HOT and will make the harness, plastic and glue HOT too... I do this without any gloves, but for those with more sensitive skin, you probably want to wear gloves.
For the 500 harness pass through connector, it is much easier to bring the boiling water to it.
First boil a big pot of water and take it to the fiero and rest it on a piece of wood and keep the hot pot away from anything that will melt. Place the pass through connector into the hot water for about 1 minute.
After 1 minute in the water, pull it back out and used a flat screw driver to pry the black and grey parts of the connector apart and remove them from the harness.
You will now be left with a block of glue surrounding the wires.
Back into the hot water it goes for another minute.
Once removed, take a flat screwdriver and lay the shaft of it perpendicular to the wires at the edge of the glue. Gently push the screwdriver into the glue seperating a large chunk of the glue fron the wires. Pull this chunk away and do the other 3 edges of the glue until you are left with just a little glue around the grey wire seperator.
Back into the hot water for 1 more minute, then pull the wires one by one from the wire seperator and pull as much glue off the individual wires as possible. Now you have a harness free of the pass through connector:
And a pile of glue chunks ready for the trash.
Take the pot of water back to the kitchen and clean it to remove any glue residue (will help keep the wife in good spirits).
If anyone else has some other methods to remove the glue from the firewall connectors please feel free to share.
