A couple of notes for those looking to replace a faulty chassis harness in a 1994 NAS truck:
First off, as far as I know, there aren't any new-old-stock harnesses available anymore. The solution I found is to get in touch with Josh at British Wiring
. You'll need to pull your old harness, carefully preserving all
of the connectors, and send it to him. If you have to clip a wire, be sure to include the clipped ends. He'll send it off to the UK and two or three months later, you'll get a beautiful new harness back, custom-made to match the original.
Now, there is one thing that you'll want to request from BW. Ask them to install the terminal ends on the forward-most end of the harness (where it plugs into the main harness in the engine bay) but ask them to not insert the terminals into the plug housing
. This will make it much easier to pass through the narrow gap
between the body and the frame outrigger. If they forget and send you a harness with the plugs already installed, it is possible to remove them by hand. First, carefully pop out the yellow plastic inside of the plugs, then use a tiny screwdriver to move each plastic barb from each terminal out of the way, which allows you to pull the wire terminals out of the plug, one at a time. Pain in the ass but it can be done.
Once you get your new harness, you'll notice that there is no fuel pump plug connector. Apparently these are NLA. No worries: order a four-terminal Weatherpack connector off of eBay and install it on your fuel pump harness. As a side benefit, it will do a better job of keeping water and mud out of the terminals, important since they hang right behind the rear tire.
I have a couple of tips for installing the harness:
Use a wire fish, like the kind electricians use, to pull the harness through the frame.
Tape the loose terminal ends to the harness with electrical tape to keep them from getting snagged. Try to arrange them so that the thickness of the bundle is minimized, to make it easier to pass through the frame.
The rear part of the harness is shaped like a 'Y', with the two branches going to each taillight. Left alone, these branches can be hard to pass through the frame. You'll want to tape one of them to the other. Whatever you do, don't tape one of the branches to the forward-most part of the Y. If you do this, you'll pull the harness through the frame and find that you can't retrieve the taped-down section because it's still halfway up the frame. Tape the two rear branches of the 'Y' to each other instead.
Take your time and be gentle with the harness. A snag could tear the wire coating and expose copper, quickly corroding your nice new harness.