> might as well be written in Egyptian hieroglyphics
It was the same for me at first but after a while it starts to make sense. Your real problem is the intermittent popping of the fuse. It would be easier to track down the short if it blew the fuse immediately, every time.

> someone having the same issue found a bare area of the wire in the harness
What some people do is replace the fuse with a 12 volt bulb then wiggle the engine harness. If the bulb illuminates you've found your short.

> get myself a chevy pickup with a small block 350

My other vehicle is a 1980 GMC with a 350 and a Rochester quadrajet 4-barrel carburetor.

 

Now thats a truck worth busting knucles under the hood. My buddy had a 78 or 79 back in high school, his was all black with brown interior and had a 5 speed tranny in it, that truck was fun...he ended up trading it off for a badass Chrysler Cordoba, from the Ricardo Montálban commercials lol, not gonna lie though thay car was effing sick af with a 360 small block in it, that car would roast some rubber! I haven't seen another one of those since back then, would be sweet to have one of them they were slick designed.


Back to reality boo, I got the starter out and the new one in now I just gotta put the wires on it and the alternator and belt back on and reconnect it as well. I got lucky and found my PawPaw's old auto test light for circuit testing I just gotta put a couple tabs into the fuse location and clip this bad boy on and it should be easier, thanks again for the schematic you provided. I got my multimeter to ohm out the parts on that schematic to ensure that they're not causing the problem.
Im also gonna run a couple extra ground wites off of the negative terminal on that starter tl ensure i dont have to get under that thing again for a while.

 

I hope you find what's blowing that 15 amp fuse. Intermittents can be frustrating. You'll need persistence and tiny bit of luck.