[Steve]

It’s been raining and storming here for the last week, and I had some extra time, so it seemed like a good time to build the fuse block for 0327. I didn’t have much to go on in trying to figure out how CHP built their custom fuse block for the 1982 Mustang, so I looked at what others have done for various years, the 1984 wiring diagram I posted earlier in this thread, and started a design.
The first thing I looked at was where I might put it. Under the dash, driver’s side, above the clutch pedal, there is a lot of room. Then, what materials were available. Any number of fuse blocks are available online, from 4 circuits to 12 or more, some very simple, others more complicated and expensive. The main problem is that, as shown in the 1984 wiring diagram, there are 10 circuits, fed by 3 sources. All of the fuse blocks I could find had provision for only one input connection. So I settled on the 4-circuit block shown in the first photo, Fuse Block Purchased, below. You can get them online from Amazon or eBay, or elsewhere. They are very inexpensive. I ordered 3; that would enable each one to be powered from the 3 sources (Mustang stock fuse block, CC1 B+, and CC1 RC) independently. I needed 10 fuses; this combination gives 12 but on two of the blocks I could just leave one circuit unused.
I had a piece of insulating board material in my electronics parts bin; it is about ¼” thick, rigid, and is ideal for mounting the fuse blocks. I laid them as shown out in the next photo, Fuse Blocks Mounted, leaving sufficient space in between to be able to run connecting wires in with spade lugs without bending the wires too close to the lugs and putting stress on the connections. I like ring and spade lugs but you have to be careful; even with the right-sized lugs, crimped with the right tool, the wire can pull out or loosen if strained.
After mounting the fuse blocks, the next step was to locate where the input power leads would come in and attach. I used a piece of solid bare #14 wire (from household “Romex” type cable to connect all the terminals on one side of each fuse block, creating a bus. The next photo, Input Wire In Place, shows all 3 with the solid wire soldered to each fuse block terminal. You have to be careful when soldering to the fuse block terminals; they were intended for spade lugs and if you overheat those terminals it can melt the plastic block. The free end of each copper wire goes to a ring connector screwed down to the board. When connected in the system the incoming power line ring connectors will go to those terminals.
The other side of the fuses are where the powered devices will connect, using spade lugs. In order to protect all the wiring from possible contact, to give a finished appearance, and enable a means to label the fuses, I needed a second board to go on top. I took a piece of prototyping board, available at any electronics supply house, and carefully marked then cutout sections using a Dremel tool so it would fit over the 3 fuse blocks. This board type is very convenient because the pattern of the pre-drilled holes makes it easy to mark and cut and line things up. It is also very easy to cut with the Dremel. The next photo, Top Cover, shows this board in place. The following photo, Side View With Both Boards, shows it in place with standoff hardware mounted in between so the top board can be fastened down.
With the basic assembly done, the next step was to figure out how to mount this assembly. Many measure, fit, mark, trim, etc. trips under 0327’s dash later, I had it figured out. By the way, I did what my mechanic friend advised if doing a lot of work under the dash: I took the driver’s seat out. This allows you to lay on your back and work much more comfortably. I even folded up a large beach towel as a pad to lay on, and it worked well. I also fabricated an aluminum mounting bracket that picks up a hole in an existing Mustang bracket used to mount a relay or a flasher, then did final trimming and fitting. Fabricating the bracket enabled a really secure mounting that gets this fuse block well up under the dash, out of view but easily accessible, while not interfering with clutch operation.
The last photo, Finished, shows the completed assembly, with mounting bracket installed. Input sources and powered circuits are labeled. I printed the labels on paper, cut them out, and glued them. I need to pick up some 2A fuses to complete populating the fuses. The unused (unlabeled) fuse positions are handy for holding spares. Final size for the assembly is 10 ¼” long, 3 ½” wide, and 1 5/8” thick. Since I had most of the materials in my shop already total cost was less than $20.
When I finish the wiring harnesses, and connect the fuse block, I will post some pics of it installed and wired.