That's what I was thinking. I've got a short somewhere.
I did buy the more expensive part.
With the old regulator on I was seeing the lights dim and the gauge move around last night on the way home from work. I did not see this behavior with the new regulator on but the system drained.

 

hi guys, i am more of a reader or "lurker" if you want to call it that.
i purchased a 75 F100 4x4 with a 390 in it a few years ago ($300, couldnt pass it up, drove it home). verified the 390 by stroke since then.
what i wanted to post here is what i am going to do when ever i have the time. i notice the voltage bounces around at idle, ok going down the road. i have extensive mechanical knowledge, so i know it is the old mechanical style regulator switching on and off. no problem as it is designed to work that way, it just bugs me. i went to the wrecking yard and purchased a solid state regulator and the connector off of a mid 80's dodge truck. i know i probably could have gotten one off of a ford but the dodge one showed up first. get the one with only two wires coming out of it and it is very easy to remove the old mechanical style regulator and splice in the chrysler one. my truck has been rolled before i got it and is in no shape to ever be restored, so a few "donor" parts don't bother me.
Aaron

 

You know what I love about our little community is stuff like this.
I know I have a problem and my expertise is in another area but the comments make you think and try to search out an answer. You get several comments and form a picture of how you need to proceed and where to look.
If you have your manure together (not that I do) you take the hints and figure it out.
It's a very cool process that I enjoy very much.

As far as the drain in the system let's assume I do have a short. When the new supposedly good regulator is inline does it not have a "shut off" for lack of a better word, that would keep the system from draining?
It seems to me that the old style senses a problem and "shuts off" until the problem (short) goes away. Then goes back to normal.
Luckily I'm at a job today I can do some research so that's what I'll be doing for a bit.
Edit:
Here is a pretty good article in case others are interested.
It was easy for me to understand because of relating the electrical system to an air system.
It also explained what I was asking about in the first part of this post.

Catalog

The question still remains why would the system bleed off with the new regulator?