cgsheen1

Here is how this one was wired: Main GND (B) is a male spade that pushes into a female held in that little box. Red/Black (RB) is the GND from the door switches. Red/Blue (RL) is +12V from the fuse box. And they're both female spades. You'll notice that the main GND can be interrupted by the switch and that the RB GND from the doors is independent of the dome switch. Now. To refurbish this one AND try putting it back together - so that it still works...

Weird - it's a turn-y switch - it rotates into or out of contact by pressing the button. That little black disc (brass contacts on the bottom side that I didn't take a pic of...) gets turned by the shaft above it. So, it needs to turn freely, have an undamaged top side (the little ramp, triangle thingy's), and the entire mechanism needs to slide / move freely, and all the contact brass needs to be clean. I didn't notice any old grease or lubricant in this one. I was surprised that the "top" was just held on by a couple of clips on either side. Everything is PLASTIC and we don't have very good luck with PLASTIC here in the DESERT, so I was a little nervous. I heated the whole thing up a bit and used an extremely small screwdriver to pry one side at a time. First side was pretty easy - the second was quite a bit harder but eventually the "top" came off and revealed the underlying surprise. The switch is indeed simple and you can test continuity straight through on the rivets both sides or the brass the rivets tie down. Also check continuity through to the bulb holders to make sure corrosion hasn't killed the circuit between the switch and the bulb.

I don't see anything unusual other than it has two possible grounds - one that can be provided by the dome switch and/or one that can be provided by the door switches. No one of them interferes with the operation of the other(s). All can be providing (or removing) ground in any combination of the three. The dome light switch itself looks fairly simple.

Hmmm, that's one switch that I've never taken apart... Now you have me curious. I think I'll see if I have a spare and drill out the rivets.

Yes on the White/Red. Through the hole in the back, attach to the screw lug in the middle right.

I saw that too...

If you need headlight buckets, I have a few.

I'm no expert but in the inertia switches I've installed I've mounted them to a hard point so any energy exerted on the unibody could be picked up by the switch.

Both are under the center dash. In the blower switch harness is a BLUE that is A/C power. And there is also a 2-pin connector with a B/W and a G for power to the fuel pump. I always put an inertia switch in that circuit.

Like the Z's here in ARIZONA...

Outstanding.

Yup, and those pillars are a bit more complex than they look from the outside. I've cut apart a few Z's and the lower center section isn't as strong as one would hope - I'm sure you're careful in it's support with the roof skeleton removed. I'll be interested in how you reconnect the center sheet metal in the pillars. There are an awful lot of people who painted over that Yellow...

Maybe this is the point where you decide which you want most - working tach or good running engine... Back when I learned to drive - and for years thereafter - cars didn't come with tachometers. They ran and we drove them all over the place anyway. (but, from the factory that car ran VERY WELL with a stock coil, a stock ballast resistor, a stock distributor, AND a stock tachometer. Just sayin')

Okay, cool. thanks for the correction.

Easy test, take the ballast RESISTOR out of the equation: Take the G/W wire OFF the ballast, hook it up to the B/W that's connected to the other end of the ballast. Run the engine. Is it better? Is it worse? Don't notice a change at all? (Better: leave the ballast out - figure a good way to connect the G/W and B/W permanently cuz VOLTAGE. Worse: hook it back up the way it was. No diff: Hook it back up the way it was - if you're sure there was no change.) (I haven't said yet what I'd really recommend which is: replace all your harness wiring, especially the engine bay harness which suffers the most degradation over 50+ years of living on this Earth... Few people listen - even me - I'm just barely doing that in my own car (and it turned 50 last year).)