This took a little head-scratching:


Could it be a GG9002A? That would be the model number for a '56 Gale built 5hp. The serial number is consistant with a Gale. Is it possible the engine is not a Fastwin, or that it's got a Gale part on it (with the ID plate). Check for a convex silver plug in the block near the spark plugs with numbers stamped into it. Anything there?

Easy enough to tell if it's a 5hp or a 7.5hp. If it's a 5hp the carb will be bolted to the side of the engine. If it's a 7.5hp, it's bolted to the front.