1st Gen Barracuda ?

The parking light issue was just a different headlight switch, I believe it was just an option difference because I've seen both years both ways. My stock 65 has them go off when the headlights go on and they stay on with the Blownfish which I reused my original light switch.

There is two different lengths in the divider panel, I've had both. But I'm not sure if it was a year difference or a difference between manufacturing plants.

I don't believe they had the Commando engines in 64, they may have had the 4bbl 273 in 64 but not all 273 4bbl engines were Commando's My car was an original 273 4bbl but it wasn't a commando.

Light switches are the same, actually they are the same up into the 70's

My 64 the turn signal lights stay on when the head lights are on. My 65 Signet the signal lights go off...... Same Harness in Signets as Barracuda's