My electrical woe occurs only when my 1994 Bonne is in drive stopped in traffic.
I apply the brakes, come to a stop and the charge drops to the red and headlights dim. As soon as I start moving the charge is restored.

My alternator and battery were replaced 4 months ago.

Don't really know how to diagnose a short....or trace one.

Any help greatly appreciated.

Please add your year and trim level to your signature. That will help us help you!

Let'* start off with the usual questions.

Is the drivers floor wet?
Have you taken the car to an Autozone, Advance Auto/Checker/Parts America for a free system test? Even a brand new alternator can go bad.

Follow all advice given above. You may also have a serious ground in your brake light circuit. If charging system & battery check out okay, commence looking for a ground condition in your brake light circuit. Will need electrical schematics for a 94.
As a starting point though, remove the brake light ckt fuse, check to see if those symptoms go away and get back to us, thank you.