Electrical problem.......

My 87 caprie has an electrical problem. Hopefilly I can get some help out there. Everything that runs off a constant source is not working(i.e. head/tail lights, cigarette lighter, interior lights, radio). However the turnsignals, brake lights, and power seats work. I have checked everywhere I know to look for a circut, relay, or fuse. I had heard that all constant sources are tied into the headlight switch and GM had troubles with them switches. Is this true or is there something I am missing? TIA

you have a fusible link blown either close to the battery or off the starter wire coming from the battery . usually a 12 ga wire with a round plastic fuse in it