Little trick as every 2nd rib is smaller than the keel width. Use the pushout ( throwaway) part from the M template for the ribs and peg onto the rib at the slot point. You can then file away till the slot is the same width as the cutout and it will protect you from breaking off the lugs. ( its in my video out shortly). Saves heaps of time and measuring.
Also wood sheet 14 is the same thickness as the keel. so test against the edge of and it it sits on it nicely then all will be good.
Also wood sheet 14 is the same thickness as the keel. so test against the edge of and it it sits on it nicely then all will be good.