Hmmm.... That's another tuff one. In Monogram's book German Aircraft Interiors Vol.1 there's one very poor shot of an He 51 cockpit and a few drawings. They're not for the float version, but I would say that there probably would not be much difference. Could be wrong though.
A not-so-quick search on a few engines netted zip in the way of cockpit shots on the web. Perhaps someone else has had some better luck?
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