Jim Pepino has plans for a 85/100" span Supermarine S6B that you may find interesting. My guess is that the 85/100" span means that you can build either size. Check out the site below. Sorry I didn't create a link. You'll have to type in the address or just search on Jim Pepino. I believe that Cornell Michaels will cut the kit for you.
http://www.fly-imaa.org/imaa/IMAAads/pepino/