Orv,

I seem to recall something about this, but not to offer as definite. The Stanzel Museum is still at Schulenberg, Texas, I believe. ...It was a few years ago when a friend visited...

If anyone could, there may be someone there who can answer. The "box-art" picture looks like a possible one-line method as follows.

E.g., consider that the lever a few inches from the inboard side of the body is probably anchored at about the CG. If the lever is pivoted on its spanwise length, and the flying line passes through it as through our common leadout guides, the lever can be rotated by raising or lowering the line. An extension of the flier's hand (visualize a short fishing pole's tip guide), can increase the motion distance. Raising the tip of the extension can rotate the lever slightly before the model rolls, or responds in pitch, to neutralize the input. That rotation could be used to drive an elevator pushrod... Just speculation...

If the Stanzel Museum can answer your question, I'm sure others would like to hear, here.

Luck!