Removing rudder

You could try cable tying the shaft of an old wellington boot or something similar to a length of scaffold pole and that should give you enough purchase to make it move then just keep wiggling it until you can turn it round and remove it. Pouring a couple of kettles of boiling water down on it might help to melt the grease that was used to install it....Good luck.

Heikki - glad you got it solved. Don’t forget to keep the special tool for next time :)

I haven’t got the exact measurement, however with the boat sat in a substantial 20T cradle the keel was about 40cm above the hard standing. At that height I could just lower and tilt the rudder shaft to remove it.  However, I couldn’t lower it completely vertically. The rudder from top of shaft to bottom edge is well over 2m.  Essentially, the boat needs to be resting: above ground level, hanging in strops or you need a floor you can dig a hole in.