WITH the engine OFF
Using a multimeter interfaced between the positive cable and the positive
battery post ON THE D C VOLTAGE setting ;testing the fuses will tell which
circuit(s) are drawing. From there it's determining which USER is BAD.

If you have a "Hall Effect" clamp for the M.M. ,used on the "AMPS" sequence
you'll be able to tell exactly which USER is drawing too much.

With the engine running place the appropriate test leads on the + and -
battery terminals ... if the reading is between 13.5 and 14.5 volts the ALT
is O.K.

Go to the FLUKE company website , there you will find explicit directions on
how to test the cables in your charging system.

YO, Brother ... H2O leaking from the ignition switch???

I'm backpedaling like mad. Mayhaps best to allow everything to dry out
for an extended time before further assault.?.