I haven't built Slow Poke, but I have built several models with a similar aileron design. I say similar, because in this type of aileron, the leading edge is built at an angle, with the hinges placed near the top.

I agree with you. There isn't enough material to bevel the ailerons as built.

Let's see if somebody, who has built this model can offer some insight. If not, let me know. I have some ideas.

Here are some pics that illustrate how I build this type of aileron. The pics are from two different models, but the construction is basically the same. Notice that the aeleron's ribs are angled, where the leading edge is attached.

Where in Iowa do you live ? I used to live in the Cedar Rapids/Marion area.