It's a .5mm fusible link 20 awg.
A 3-5 A fuse and holder should work or make the right one up.
https://www.oreillyauto.com/detail/c/standard-ignition/standard-ignition-20-gauge-fusible-link-universal/std0/cw20f
If it's a Bob Bailey two-step box, I don't have one so I don't know, then this may help.
http://www.bailey-eng.com/2step/Manual%201.0.1.pdf
And a wiring sheet from the Turbotweak site.
The fusible links for the factory fans can be tested at the low and high speed relays on the drivers fenderwell area, fat red wires on those relays should have power +12 on them at all times direct from the fusible links.
Aftermarket fans that need more power are usually wired to the battery...
Drop the glove box it's right behind it. Terminal J on the big connector shown in the photo with the fuzz on it should be the orange wire. One side goes to the ECM the other to the ALDL port. Serial data line. I would ohm it with connectors unplugged at the ECM and nothing plugged into the...
Does the car have the factory computer, lots of race cars had aftermarket systems?
That orange wire from the ALDL port goes through one connector C437 behind the glovebox to the ECM directly pin A8 of connector C2 at the ECM in the Pass. kick panel orange wire color all the way there.
Caspers sells a PARTIAL harness that should get the engine functions working. If the dash harness is bad what about the engine one that needs to work too?
https://www.casperselectronics.com/cart/index.php?route=product/product&path=7_53_54_10_16&product_id=697
Mines under the radio where it's supposed to be.
Two row connector with mounting tabs.
You need two black connectors that plug into the white C437 connector A-H and J-R.
None that I can see go through another connector, I don't think that connector has anything to do with the ALDL port.
The ground wire goes to the ALDL from a spice in the harness, the other ALDL wires shown on these pages go straight to the port from C437.
Post up a pic. of the C437 connector...