On my 05 Sportster, there is a circuit board that the tail light and flashers plug into, just behind the tail light. Is it necessary? Or, is it more of a convenience thing for removal of lights. I have some clearance issues with my new set up, and if it is necessary, I will have to do some relocating.

I believe its just a contact board.....I don't believe there are any active electronics there.....however, I don't know the newer bikes....

It is just a circuit board. I totally removed mine when I rewired my '04.
Just have a wiring diagram handy. By the way, you'll find a "spare" hot wire back there off of the "accessories" fuse.
Andy

Sweet...thanks for the info guys!

that was a great question.
those small things are always nice to know.
It helps us all learn something that we probably would not otherwise ask.