Headlights and tail lights drawing to much power! Help

inertia said
Check the belt for wear and adjustment,, a loose belt will cause similar symptoms..

but discharging at idle with lotsa things turned on,, is not un-common, as mentioned..

Bad Sport said
Loose belt, bad grounds may cause undue strain.

Check and clean all fixture grounds, front and rear. Make sure battery terminals are clean. Make sure battery and alternator are good.

OMG, you two nailed it.
Bit by my own philosophy (Start with the easiest thing first) :D