Help - no parking/tail lights

I have a 81 GMC stepside that the front parking lights, rear parking/tailights, interior dome lights and gauge lights will not work. The headlights, front and rear signal lights, brake, back-up lights and flashers
work perfectly. I've checked and replaced all bulbs and the fuses all look good. I've looked and can't find any damaged or broken wires and have cleaned all the grounds that I can find. The headlight switch has also been replaced. I have power going into the headlight switch, but nothing is coming out when the switch is pulled halfway out for the parking lights.
Any suggestions to help fix some or all of these problems would be most appreciated.
Chris
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circuit those years and has its own feed from the battery. The rest are feed power via fuses. The dash lights are a 5 amp fuse in the lower left of the fuse panel. Above that will be three 20 amp fuses and a circuit breaker in a horizontal row, the center fuse is for the tail lights and courtesy lights. There is also the possibility that a fuse link has blown at the starter, does cigarette lighter work?
Whitelightning
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The cigarette lighter doesn't work either. I forgot to add that in the original post.

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junction box on the fire wall and then to the fuse box, it has a splice that goes to the plug on the Alternator, the other goes direct to the fuse box. with a splice off to the alternator main terminal. So an easy check is a test light on each red wire on the alternator.
Whitelightning
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