On 1973 Ford LTD. Battery (new) runs down over night with no accessories on. There is high current flowing between negative post and disconnected negative cable. Pulling fuse for each circuit does not reduce current flow in negative cable.
Sounds like a diode in the alternator has gone bad. Given the way the alternator is tied into the system removing fuses does no good. Have the alternator tested and if need be repaired
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