I am making the forms for a Guillemot from the offset tables in "The Strip-Built Sea Kayak" book. (Great book) My question is about reference lines. The suggested lines are CL, DWL, Diagonal line, and sheerline. All my lines are perfect except the sheerline. In photos in the book there is another line that seems to be a reference line above the DWL. (pg 71 fig 5-19, pg 72 fig 5-20, pg 75 fig5-27.) Isn't the DWL the common line on all the offsets? Should I just create a second line, maybe three inches above the DWL as a second reference line used to keep the forms straight.

Also I am a larger person. 6foot one inch 250 lb. I am thinking of enlarging the forms to "fit me a little better" maybe 21 inch beam to 23 inch beam. Has anyone tried this? Thank you for any information you can give.