ADDING SIDE MARKERS TO A '67 BARRACUDA - Locations and wiring

Yeah, it's your car. Recognition for other drivers, lights or no lights, Moot. Look at how all new vehicles headlights are so damned bright and aimed high, glad that they can see, everyone else is blinded and can't see anything, but that won't be your problem.

Honestly that's not true, it's not moot. There's literally an entire DOT study linked in this thread that says side markers reduce accidents by 100,000+ a year. That's significant. Maybe they aren't the high speed, driver runs a red light kind of accident since the fatality number wasn't effected, but being able to see the side markers clearly prevents some lower speed fender bender type accidents. Not everything is a high speed intersection, starting from a 4 way stop in the dark a side marker might just be enough to keep that other lane from rolling through out of laziness, and that could be all it takes.

His car anyway. My Duster obviously had side markers on it before, but adding the '68 markers is about as easy as it gets to add an actual marker light. They're Mopar parts, they light up, and you can do the work on a painted car if you're careful with some masking tape and use a sharp step drill.

For colors and wiring the '68 Plymouth service manual is available on mymopar.com