Bill-- I have no technical suggestions to offer, but can tell you that it's possible to do it. I got in a lengthy discussion with a pilot at our local yearly airshow (Warbirds Over Hickory) who flew in in a Helio Courier, and later demo'd the STOL and slow flight characteristics of the plane. As you may know, it utilizes a set of leading edge slats, that deploy on the principle that BMatthews was talking about, but they are not spring loaded on the Courier, they have a curved track and open from their own weight. Anyway, when he learned I flew R/C (I was asking about availability of plans for the Courier), he told me of one of his fellow pilots (they fly mission flights for JAARS) who builds not only giant scale R/C planes, but ALL ALUMINUM giant scale R/C planes, and had built a 1/4 scale Courier with functional leading edge slats. This guy is from South America, he has a website called
www.allmetalplane.com You may be able to contact him for the technical info you need. His planes are awesome, check them out.