Arno,
I'm building the F85SR. The closest to this design is the F82R.
Towards the bow there appears to be a difference in deck shape as you have noticed in the photos of my F85SR floats.

Ian would be the best person to direct questions to about the design if you want more detail.

Regards,
Phill

I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!