[Alan in AZ]

Sounds like you have many instrument pod issues - did you remove the pod for some reason? if yes - maybe the connections arent correct - I'd suggest you check/clean

Your headlight issue (one side) sounds like a ground problem (or connection problem) to just that headlight. It is not likely what killed the alternator.

Check ther alaternator voltage with a reliable meter - thats the only indication of goodness.

Nothing else on the car can really cause the alternator to generate a sustained too high voltage - its self contained. Assuming the battery is good enough to start the car - its good enough to work properly with the alternator/regulator.

The high/low beam switch is not the same for all years (though its similar). You should not have needed to remove the pod to replace it - but if neither switch works correctly it may actually be the headlight relay that is at fault (its what actually switches the beams). Again not all years use the same relay - check.

Alan