I’ve searched and searched and can’t find a clear understanding of how these will splice in based on wire color. The FIC pig tail has red and black wires. The stock NA harness has white/red stripe and maybe yellow. Not sure if the polarity matters or not. Thoughts?

 

Polarity shouldn't matter. white/red is positive.

 

yes, I decided to order the plug n play harness instead. Last thing I need is a bad connection.