That will be quite a beautiful piece when finished and I realize a lot of work went into it so far, but it would appear there are some errors either in the photograph or in the casting.
The fuselage top of the Seamaster is straight on to the the vertical fin, not angled up after the wing attachment point as your photograph seems to show.
The wing tip floats are under the wing tips, no?
One last issue would be that the rear exhausts of the paired jet engines on the actual aircraft are quite noticeably rotated out from the fuselage sides. Hard to see if yours does that or not. There is a photo of what I mean in this short summary- also shows the straight top of the fuselage.http://www.aviation-history.com/martin/p6m.html
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