Norfolk,
That prop should be ok. It's a little lower pitch than OS recommends for the engine, but I think you'll be ok. Here's what I do to keep my engines running a bit rich. Tune it for peak RPM, and then richen it 2-3 clicks. If you do this the engine should leave just a slight smoke trail in the sky, and will be rich enough to protect the engine. As I said, you may loose a few hundred RPM. But the engine will last a lot longer doing it this way.

Ken