Nothing bores me and annoys me more then wiring. Which is why I struggle to even do updates during this - HOWEVER, I think this time there might be things which need enlightening - so, in the interest of advancing knowledge, I persist.
It's always a bit of archaeology to try to figure out why... in this case, why did they run half a light cord from the alternator to the battery? it does explain the jumper cables.... but why?

why didn't they attach the signals to the grill?

why did they put ANOTHER relay when all they had to do was put 12v to the pink wire?
First explanation. The GM controller is a relay. It has a sensor in the coolant that opens at 152*, it fails in the open position (thus not burning the glow plugs down and causing catastrophic failure of the motor when the plugs melt then the glow plug wires catches on fire and burns the vehicle down)
Originally, GM had a sensor/controller on the 5.7 then the 6.2 (shared parts, there are few but that was one). That gem/jewel was one-piece and would fail then cost 175 to replace. In 1985 GM finally heard the whining and came up with this controller. It has a separate sensor and what you see (the blueish bit on the motor) is mostly a large relay. It's also easy to bypass - though likely it's simply the sensor that failed... still $100 to replace, but not so bad as before - even if one does replace it. Put a momentary switch in the cab just in case... and send power to the larger of the pink wires.
hey look, less color

much better

the pile is growing

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next issue is these wires. the white one is for the tach (which they destroyed when they replaced the motor), the two coated wires are amazingly thick, but ulimately 20 gauge wires for the dual fans. I don't like electric fans, I think they create radio noise, draw tremendous amounts of power, and don't cool as well as an engine driven fan.... after all, an engine is whatever the hp is of the motor (180 hp in this case). The dual fans are may 2 hp. 2 hp is not as powerful as 185 hp. Granted, clutch fans fail and do so at the worst time - but I'd rather run a screw through a clutch fan to make it a direct fan before I'd ever put an electric fan on. With that said, having electric as backup is a great idea on a 4x4. In this case, they put it on the wrong side and I'm simply too lazy to change it.... so that will be fixed, but in a far better manner then a relay wired with house twist ties.
Wiper motor..... I didn't know before tonight whether or not it was simply the wiring or the motor was junk. I suspected the motor was junk because they had an aftermarket controller on it. Turn the wipers to high, then adjust the knob to get delay or low wipers.... I can't imagine the controller cost less the $25.00 and a new, rebuilt wiper motor is $55. Not sure why, so I suspect that I'll be replacing the control board too ($64) .... but one step at a time,
soldered the wires together and shrink wrapped it...

fixed
more puzzling - why did they strip 2" off the fuel pump shutoff?
ah well, liquid coating was made for these issues
Cruise control
I found this laying in the back of the motor
for whatever reason they felt an arrow shaft was the appropriate vacuum block-off rather then having cruise control. There will be more on this later, when I get the accumulator and check valve - but I will fix it. Cruise makes long-distance driving a much more enjoyable endeavor....