Unknown antique two cylinder, two cycle engine

Looking for info on the maker…unknown at present. We believe this to be either an early auto or aero engine. Made around 1905 based on use of 1/2-12 fasteners. This is a three-port, two cycle engine where the piston skirt valves the charge going into the crankcase. The flywheel end of the crankshaft has a tapered section for the flywheel to mount. The flywheel is probably not correct as we have no clue what was originally on it or if it was a propeller as used on an airship or aero plane . May also be an early auto engine as evidenced by the mounts. Use of so much aluminum in the crankcase is unique for that time period.