Thank you for your replies.
About measuring : unfortunately I have a hard time trying to be sure about the exact distances. What's sure is that it has to be more precise than half a millimetre. I do not have tools that are precise enough.
About scanning and rescaling... I could do that (and already did in the past for other gear), but if someone (Mr Dieter Doepfer perhaps ) could give the exact dimensions, that would be far better, more precise and faster...