Cadillac Repair: battery drains overnight, negative battery cable, josh gorman

Question
i have a 88 cadillac eldorado.  i just replaced the battery, twice, just in case it was the battery.  every night when i park it the battery dies.  have diconnected the negative terminal with battery charged up well, hooked a test light to the negative battery terminal and the test light probe to the negative battery cable, and the test light is pretty bright.  Brighter than it should be.  I then started pulling fuses, from the fuse box in the glove box, in the egine compartment, as well as the fuse box under the dash.  While pulling every fuse as well as every relay, the light does not get brighter or dimmer.  I also put the key in the ignition and the light got brighter, which i though it should have gotten dimmer.  any help would be greatly appreciated.  Thanks, Josh Gorman

Answer
OK, You CANNOT use a test light on a car with a computer as the comoputers ALWAYS draw 1/2 amp from the battery at all times.

Hook up an amp meter between the NEGATIVE battery post and the NEGATIVE battery cable and see how many amps you are drawing.