Burnt Wire

shittyslant6 said
Now, the only thing thing that happens is the ammeter discharges to -40 when the key is turned to the start position.

WHY ARE YOU DOING THIS ?
Over 40 amps in those wires IS going to damage something. Probably several things.

We gave you two safe ways to track down the short. One disconnect the battery and use a multimeter or continuity tester.
OR install a lamp in the circuit.
From your earlier post I thought you understood. Specifically this:

shittyslant6 said
So,
1. put a big lamp in the circuit to limit current so I don't fry anything else.
2. then I put the key in Start position and start looking around for shorts. VR, ballast, etc.
3. If nothing turns up, inspect the start/ign. switch and check for shorts or bad ground.

shittyslant6 said
I am thinking that it is either the start switch or the ammeter is bad.

Its highly unlikely the ammeter. Quick test of the ammeter is to step on the brake, turn on the dome light, or turn on the parking lights. The ammeter will show current flowing out of the battery for any of them. None of them individually draw a lot of current. With side markers the parking lights maybe add up to 5 amps. See how much the needle moves. Then you'll know.

It's possible that its the start switch.
The way to find out is either with a test lamp or a multimeter.
With whichever one you are using doesn't matter.
Disconnect wires one by one until the problem goes away.
I think 67Dart273 suggested begining at the starter relay. That's a logical approach.