Little Auk 10 cockpit width

I’m getting ready to deck a Little Auk 10. I cut out and placed the cockpit pattern on top of the forms and it extends a good 1-2” past the top grooves in the bulkheads (which, I understand, are supposed to show the extent of the cockpit). For instance, at the middle bulkhead the groove is 16 1/4” long but the pattern shows the width there as 19 1/4” (measuring straight across). I did notice the drawing I got with the kayak was for the Auk 11, so maybe the cockpit pattern is for that, though I’d be surprised they would be different. Can anyone tell me which is correct?