Those are all fuse 12. Pull it, clean it, replace it.

The dimmer (aka rheostat) is off fuse 1. A busted rheostat is a common problem. Search and you'll find how to jumper it, or how to clean it.

Some other possibilities might be a sticking or dirty hazard flasher. Cycle that a few times and see what happens.

Or - a botched aftermarket radio install. The 240's didn't have a hot wire, so they get hacked into to install one; but the radio did have a connection to the headlight dimmer, but people work during the day so that wire looks dead, or maybe as ground, so it gets misconnected with the new radio. Then someone messes with the dimmer - or the shifter lights - and kaboom - hard-to-diagnose electrical weirdness ensues.

Also - check your taillight sockets. Using the wrong bulbs in the car (eg double filament HD bulbs) can get those hot and melt. This is usually more a problem for taillights than brake lights though, since they're on for longer periods of time.