How are you cutting the first circle? If you're using a jig, overlay the two baffle pieces and line them up. Drill the center hole for both at one time. Cut the same size circle in both and they will line up. If you don't have a jig, but have a router, cut the first hole to size and rough cut the second hole undersized, glue/screw the two pieces together and use a flush trim bit in the router to match the two holes.