Hello Cougar community… need help bad i recently purchased everything for the led upgrade…new turn signal switch,2-flasher units, side marker led kit, and the solid state led taillight sequential unit… Having issues now everything works except my taillights are not sequential …the bulbs are on but nothing flashing…my side marker lights work. the front turn signals work. they all flash with the hazard lights on except the taillights…
I’m assuming you bought the parts from WCCC, below is a link to their video with Richards 71 where he discusses some possible issues. Starts on the 71 about 3 minutes in. If he doesn’t mention it you can always give those guys a call. 
Thanks bud i did purchase everything from WCCC and watched that video multiple times lol… i called WCCC and one of the guys said i may need to use their bulb which they are out of stock of … i used Sylvania 1157r not sure if the compatible with their unit
Laughing, ok I was just starting from scratch on the troubleshooting. Yea probably other bulbs are not compatible, I haven’t done the swap on my 73 so can’t offer any more help. Maybe someone else will chime in
I heard WCCC should have “their” LED bulbs back in stock within a week. Suggested you log into the web site and click “the notify button” to be alerted when they arrive