I hear ya on the un-metered air thought. I have the same concern with my manifold and found the flange on the runners to be leaking at the head. Maybe that's your problem. I doubt leaning on it will hurt it, they are pretty solid castings...
Isn't Steve Shadows in California. I would love to have someone like that check mine out, but I'm based in Georgia so there isn't THAT much around here... unfortunately
this is what my setup is like...
