Im about to rewire my car and..

I have a couple of questions.

As a background, POs already had rewire the car, so there aren't any traces of original color wiring, connectors and terminals. The car also doesn't has the reverse switch, courtesy lights, glove box light, heater, nor horn.

Here is the schematic I made of the wiring I just took out of the car:

<a href="http://s54.photobucket.com/albums/g81/Dothang67/mustang%2067/?action=view&current=POMustangwiring.jpg" target="_blank"><img src="http://i54.photobucket.com/albums/g81/Dothang67/mustang%2067/POMustangwiring.jpg" border="0" alt="Photobucket"></a>
Why are the back-up lights being connected to a "always hot" 12V source, I really don't know.

I plan on improving some things like adding a fuse panel, and making all the wiring color-coded, but I probably leave most of the connections the way there are IF they are correct (thats why I want to make sure its a good wiring).

My questions are:

1. There is a circuit breaker going to the Light Switch, this is a 30A circuit breaker; does the Light Switch can handle that load, or should I put in a lower amperage circuit breaker? Or maybe change that to a fuse?

2. In all the diagrams I have seen, there is only one cable going from the Starter Motor to the Starter Relay. Why do you think mine has two?

3. Do you notice anything important that I should address before I start rewiring the car?


Thanks in advance

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GEN = Alternator
MC = Voltage Regulator

I have everything to start rewiring the car, even come nice connectors I found, so buying a harness is out of the equation; even though that is what I wanted a few years back.

Weird, maybe one of the POs had also a GM car and thought that was the way to go.