1984 Rabbit Convertible Woes/Introduction

Hey guys, I'll keep both the introduction and question short (kinda).

My names Steve, currently working on an 84 Rabbit Convertible that I've had sitting around for a good 7 years. It was my first car, bought with MY own money, title in MY name, all that jazz.. She was 'rigged' by some guys in New Jersey just good enough to sorta run. Bought the car for $500, after a good $1100 all together, here she sits. Overheating. Still.

Lets start with the previous owners crap. Claimed it was its 2nd motor, still a JH 1.8 CIS, this one HAS A/C. Einstein stuck a spark plug that was a bout 1/8 inch too big and stripped the spark plug hole to hell.

So we bought a new head. Head was fine, new headgasket. Good compression and the car ran fine for a good 9 months.

Took in out on a drive and it overheated to the point coolant was boiling out from under my closed res cap. Parked it up for a put a new waterpump in it, new hoses, flushed the rad did all that. Car ran fine after that. Made a bit of a mistake when wiring a new aftermarket radio and fired my dash wiring up pretty good. Then it sat, for years until recently I got my interest in the Ole Girl back.

I undid the burnt wires, and replaced them. Re-ran them so them weren't so bunched up and cleaned up some connections all the way around. Eclectically, in the dash wise, the car seems alright, except my tach and cluster seem to short(?) when I turn my highbeams on, my tach and gas gauge stop working completely when my highbeams are on and my coolant gauge, although the needle still reads my light seems to come on, as if I just turned the key. Also when the key is turned to ACC or 1 click my tach jumps to about 7000 RPM and dies back down, it seems to be running off my fuel pump for some reason, the tach needle fluxes with the buzz of the fuel system prepping. I think I have that pin pointed to:

That. A really crap lead that seems to touch on to at least one more.
But Thats not my issue here.

Its my overheating.
I've replaced the waterpump some years ago and then the car sat, recently bought new hoses, new thermostat, and a new fan switch.

The switch I had, a 2 pin 95/85 switch ran into a 2 pin single speed fan. It worked for a while until things got weird. I got it reregistered and insured so took it out on some short road tests, then the long test, 45 mins to an hour out, at a red light my belt started squeaking like it was slipping and the car seemed to sort of died, I quickly restarted it with no problems and went home, didn't think too much of it until the next day, went out for cigarettes not 2 miles from home and my gauge spiked to the right and the temp light came on.

Quickly turned around and parked it.

--->What would cause that belt to squeal like a pig and the car to die like that?<---

The squeal could of been (what I think) an air bubble trapped somewhere that made its way to my water pump, making the pulley not move and the belt to squeak, the air pocket or pockets could also of been near my rad fan switch, making it not kick on, and thus overheating and such. After a few test runs the fan never kicked back on after I tried refilling the coolant.
I tested the switch in boiling water with a voltmeter and it did its thing at the right temperature so I know the switch is good, I tested the fan but I think my jumper wires are trash, when jumped the fan doesn't kick on, but when wired into the harness itself, HVAC on and set to A/C the fan turns on, so I'm assuming the fan is also good.

I added an aluminum thermostat housing, because strength, and I've got the correct thermo in there. Since then I've taken the radiator out and began flushing and testing wires.
Last time I had the car running to see if the fan would run I noticed my upper rad hose and waterpump being hot, while my lower hose was cold. Now, I just need to refill the system and try it out again.

Now a second question about wring for those who read this far..

Like I said before 2 pin 95/85 fan switch, 2 pin single speed fan. My theory is get myself a lower temp switch to combat the PA weather, but the only low temps I've found are 3 pin.

I take my current set up, which pretty much besides looking like a 5 year old drew it, looks like this.

and use the 3 pin fan switch with the 2 pin fan. That red and white wire, which I assume is a speed setting for the 2 speed fan has to go somewhere, or can it be deaded? Where would I have to splice that to if I did infact try and run a 3 pin fan switch? Again, ASSUMING it would just get hooked into the red/black +12 that comes out of my fuse block and into the fan? Correct me if I'm wrong.