Oh man Mike, that turned out super. You are such an amazingly fast learner. Anyone would be proud to own that beauty.
The only two suggestions I have are extremely minor, and are a total matter of preference. I would put a coat of cold blue on those two patch box screw heads, as to my eye they call attention to themselves versus the well crafted patchbox. The other is that I'd rub a coat of oil into the iron mounts and lock. It appears from the photo that you have active rust on the cock and a few other spots. Like I said, very very minor comments.
Overall, you nailed it buddy! Send it to me in NC for testing. :-) I have a Jim Webb bag here that would be good to feed it from. God Bless, Marc