I return after a brief hiatus to conclude this post.
See the few new photo's to see what I found.
I managed to extract the splined shaft from its Bearings and came out with the chuck attached.
That involved a LOT of pounding. (Careful pounding of course..)
After unsuccesfully applying a Gas torch I resorted to complete anihilation of the chuck with an angle grinder and eventually I was presented with a B20 stub.. huzzah..!
So.. NO Morse taper..
I still do not know what purpose the knurled nut played in the scheme of things.. It may have been broken..
I Tapped the B20 stub to accept my new chuck and re-assembled with relative ease.
The only blood drawn was when I was removing the Hand wheel shaft and it suddenly dis-engaged the coil spring and the containing 'canister..' flew off and the spring caught my little finger.. Ouchie.. I then discovered a little grub screw which holds the spring canister in place (See pics).
The spring canister has 2 x 5mm holes through the cover to be used with an appropriate pin tool (Like an angle grinder spanner..) to rotate and re-tighten the spring and then the grub screw to hold it in place.
Overall I am glad I did it at zero cost as it is a substantial tool and the long quill proves very usefull.
Thanks again guys for your assistance.