04 taillight troubles

[DDoctorian]

The rear clearance lights on the drivers side wont light on my 04 dually. Stop and turn work as do all of the trailer lights, stop, turn, clearance. The "lamp out" light on the dash does not light unless one of the bulbs is removed. The bulbs are good. The fuse under the hood is good. The clearance lights in the fender (dually) dont light either. Anyone have any idea what and how to find the problem. Your help is much appreciated. Thanks.