Hi
I used to own a Wilson Flyer 17
Mine was a bit heavier built than the usual layup
I originally fitted it with an old 45HP and it was a lemon, engine change to a new 60HP 2 stroke and it was a different boat, back to a flyer.
Later on I took out the bulkhead and lifted the soft floor, doing so I found some foam under the deck that had soaked up water over its lifetime. Removing it was a pain but it was so heavy that it had to go.
new flooring fitted and a console instead of the bulkhead made my old boat a hell of a lot better. the reduction in weight made a huge difference to speed and economy.
You need to get that wet foam out Ash, before deciding if the engine is big enough
Hope that helps