RE: Sterling Stearman ?s
It just ain't a Stearman without the radial engine hanging out there. Here are some photos of mine. I used the plastic engine that comes in the kit. This plane is still flying after 15 years, and the dummy engine has held up well. I did reinforce it with expandable foam inside the cylinders, and dowels cemented between cylinders to prevent flexing.
OS 91 4 stroke for power gives very scale flight, but it is a heavy plane with lots of lead in nose for balance. Probably would be even better with a 1.20. If you balance as per plans it will fly well. Just don't be surprised at how much nose weight you need.
Mine is covered with combination of super coverite which is painted (yellow surfaces), and Permagloss (pre-painted fabric which is no longer available).
If your hinges are pined you can cut off the ends of the pins and separate the surfaces for covering repair.