It really sounds like there is a live (perhaps a chaffed power wire) wire going straight to ground somewhere. Has there been any recent work (other than as described) that may have caused a nicked wire or something not working that should be?
First, remove the negative battery cable, and connect a current meter (or test light) between the negative battery post, and cable. Remove one fuse at a time until the current drops (or test light dims). This will help isolate what circuit is drawing too much current. Normal drain current should be in the 25mA-50mA (0.025A - 0.050A) range.
no work has been done, other than what i have done. I put a voltage meter on the battery, started the truck, had 11.97, turned on the head lights, went to 11.80 and held, turned lights off and it built back to 11.97. but pulled neg. cable from battery, and it dies
Your alternator is not working. Also, a suggestion: Do not remove either battery cable when the engine is running. Voltage spikes will be generated from the Di/Dt that can damage electronic components like PCM, etc. .
So, it looks like your battery drain is due to the alternator not charging the battery.
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