All,
Thank you for your quick reactions.
I am now a lot wiser about conversions, long nose, short nose and cup noses.
PH-CGB was converted to CV-440-4 standard in early 1955.
This must have been only the engine (exhaust?) modification as I also see the same full metal short nose with pitot tubes on photos with the Jan Scorel in the later 1960 KLM livery.
so the conversion date is not decisive also because I think 1955 would have been to early as my father in law would have been 7.
The search continues.