New harness problem

First, I assume this is supposed to be a factory equivalent harness, as opposed to something like a Ron Francis?

Second, are you talking the entire car, or just part of it? The harness I mean.

This sounds pretty serious, as in, something got hooked up wrong, or the harness is defective

I would go after the hot cable first.

When you say you put the key into the "second stage" what does this mean?

Are you in "run", "start", or "accessory"

I would rig a heavy lamp, such as a stop/ tail lamp in series with the battery, so that when you put the key into whatever you mean by "second stage" You can SEE the lamp and the lamp will protect the car.

Start by disconnecting the ignition and regulator. If you still have a lamp, something in the car is either on or there's a short.

Make sure EVERYTHING in the car is off, radio, heater, interior lamp, etc.

Now pull fuses one at a time and see if the lamp goes out.

If not, start pulling major connectors off the main harness.

Pull the connector for the rear tail lamps up near the kick panel

Pull the turn signal connector at the steering column.

Continue down this path until the lamp goes out.

When / if it does, check that section of the harness

You have a shop manual / wiring diagrams?

Download factory manuals here:

http://www.forabodiesonly.com/mopar/showthread.php?t=132309&highlight=manual,+download

or somewhat "alternative" wiring diagrams here:

http://www.mymopar.com/downloads/1967/67ValiantA.jpg

http://www.mymopar.com/downloads/1967/67ValiantB.jpg


Another good tool that once in a while comes in handy are these "short finders" I'm not recommending this one, just an example:

You put it across a fuse, and it cycles on/ off like a breaker. The meter finds the wire drawing the current by causing a magnetic field, sort of like a wall stud finder

[ame="http://www.amazon.com/Tool-Aid-SGT25100-Short-Finder/dp/B002XMUGZC"]Amazon.com: Tool Aid (SGT25100) Short Finder: Home Improvement[/ame]