Good luck! As you suspect, so do I, that this isn't a flyer. The flyer moulds have an extra chine or 2 (2 on the 20) that makes them distinctive. Good luck with the build. First thing I'd do if go weigh it and see what weight it is at, give you a clearer idea if it's full of water. Plus cut some hatches in to the deck to look for water. Engine wise, how about a pair of 40's or perhaps bigger? I'd have thought you'd want 100+ hp from single and more if twins. Enjoy!