I'm replacing the speakers in my Mazda 3 hatchback grand touring. I don't have the BOSE/moonroof package. The front speaker harnesses have 4 wires. Two red and two blue. I was told red is + and blue is -. I think one of each might go to the tweeter. Should I solder the blue wires together, and the red wires together, then connect the red bundle to + on my 5x7s, and blue bundle to the -?