Yup, that's exactly what's wrong. It's the key switch its self. the connector (upper right, always hot?) is melted almost out of the plug, right? Same thing happened to me, just that mine kinda caught on fire before I paid much attention to it. Fix it ASAP. The thing that kept it from happening again was that I put my stereo circuit on a relay along with my CB. Much less load on the switch.
lol, 3500 Dodge trucks from the late 90's have somewhat the same problem (if you have the heater going full blast, the windshield wipers going, the bun warmer on, and then you think you need the window rolled down, bad things happen...)
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