Adding to the Wiring Harness, I could use recommendations Options

[Literati914]

Just trying to think ahead - I’d like to add some extra wiring to my original ‘72 wiring harness before I re-install it into the car. I always struggle with electrical stuff but usually manage eventually.. but I was hoping for some recommendations to try and eliminate any “ooops!” moments later.
Im gonna have to figure out stuff like preferred gauge of wire, inline fuse/relays, is a ground wire needed thru the harness for particular items, etc.

1. A/F Lambda sensor: both a + & - wire needed thru the harness?..where should it ground?..what gauge wire?

2. 3rd brake light: same questions ^ , also can I just tap into the already present stock wire for rear brakes?

3. Oil pressure numerical (for combo gauge), I’ll be using a dual pole sender at the engine: same questions^ and where does it ground?

4. CHT: so I think I’ll only be adding the specialized braided wire to the harness - is that right? Does a ground wire come in to play somewhere?

5. Fog lights: I need to look closer at my original harness (‘72) but I don’t think the car came with fogs originally. So same questions as above ^ .

6. Positive Battery Cable: so, rather than have a bunch of wires attached outside the + battery terminal , I’d like to get them imbedded inside the harness and shrink wrapped into the + cable’s outer shell. I believe the radio is usually one that you see here (what gauge?)… and what are some of the other stuff we usually see attached to the + side (IMG:style_emoticons/default/confused24.gif)

Any help appreciated!


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