Crowther trimaran advice

The guy next to me in the boatyard has a Crowther Kraken 33, (and little/no computer access) so has asked me to seek help for him.
He is trying to remove the centreboard, only it won't come out via the top - the previous owner says it has to be dropped out the bottom. When being raised it hits a definite "stop"and all manner of poking and prodding with a thin stainless strap down the front and back edges have revealed little.
Has anyone got any plans showing the centre case details which prevent it being pulled out upwards and which might give him a clue as to what to do to modify it so it can be pulled out upwards.
Seems a bit stupid to have a centreboard which can only be taken out underneath, great potential to even lose it while sailing.

 

I am conversant with both the Kraken and Buccaneer 33 and I can't tell you why.
It must be due to some previous owner who made changes to the design 'cos
the K33 and B33 plans show dagger boards which can be removed from above.