Hey Bruce,
Really going after this aren't you?? The P19MX giving you a hard time? LOL
This may help you to some degree. From what I have "readily available" Randy stated that my MX main was 190 sq. ft. The MX jib was 75 sq. ft. IF my memory serves me correctly the "stock" jib was 57 sq. ft. and the pin head main was 175. I remember looking up the total sq. ft. on various boats, and it is pretty darn close to the Nacra Express. I'm probably pretty close, but I'll dig deeper in Smyth's folder. If I made a mistake, someone will correct me...that is fine.
LOL,
Dave