The serial number says 1914. All the parts are correct for it with the exception of the exhaust, so I would say you have a 1914 motor but the exhaust manifold and muffler can are from a 1915 or later. You need the earlier manifold that does not have the water plumbed into it and a muffler can that has two triangular hole patterns drilled in it.
Hope this helps.
Best,
PM T2
He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...