Personally, I‮d steer clear of a sailmaker who puts the onus on you to provide accurate measurements on a boat that has pretty standard measurements and readily available class rules, unless you don‮t have a stock rig. Also, if you aren‮t going to race OD, I would consider a full length luff for the #3 vs. the one design max length. Shouldn‮t be a hit in phrf and also lessens the sail area gap between the #1 and #3.