Turn signal electrical issue 1970 Mach 1

[flananuts]

Maybe some info in this thread  https://mach1club.com/showthread.php?tid=7907

Thanks for passing that along. My left side marker light doesn't work so I'm wondering if that is where the two lines are grounded/shorting. I didn't want to do it but I'm going to clip the wires to the side marker and front left park light to see if the issue stops. I'll know because my hood indicator light which is further up stream on the loom lights up solid when the park lights are on. That will at least let me know if those assemblies are the root cause.  

Cheers