Brian,
I know the feeling about posting into empty space. But, although you don't have many replies there are a bunch of us following along. You have over 2500 views on this thread. I should have posted earlier but because of a medical problem typing has been difficult for a few months so mostly I have just been reading the posts.
If you have seen any of my threads on opposed piston engines you know that I like to model things that are out of the ordinary. It's a lot more fun to make something new from some crazy idea in your head, and inspiration can come from so many things that have been tried in the past and never really caught on.
Keep it up
Gail in NM