Sounds like a wiring cluster puck and muck to me.
I am goiing to color fish finder this year as well. I guess for the money you can get a cheap combo in black and white. Might as well have a back up. Makes sence. Wait, I sound like the two old guys on the mupets. "I HATED IT!" "YEAH THAT WAS AWFUL!" "IT REALY WASN'T THAT BAD" "NO NOT AT ALL" "BRAVO, BRAVO!"