I've attached an image, with data from Andy Lennon's book, "The Basics of R/C Model Aircraft Design", which shows the proportions.

This also gives me an opportunity to mention that I've created a set of web pages which details many kinds of high-lift devices, at http://homepage.mac.com/mikejames/rc...ite/index.html This (free and non-commercial) site already has several contributions from RCU members, and I encourage you to share your progress with us, so I can add it to the "Contributor's Pages".

Good luck!