Hi. That is definitely NOT a Grand Prix engine even if you ignore the obviously faked number. The 1934 GP engines have a much larger crankcase door opening diameter, and originally had the magneto mounted on the left hand crankcase door and driven via a bevel drive arrangement. On the right hand door was a very complicated swashplate oil pump. This machine would be useful as a source of bits to build a racing Scott but it is not a Grand Prix Scott.
Regards. Brian Marshall.