Thanks very much for all help guys.
Along with clutch I also replaced all these parts that was suggested in this post along with replacement oil!
Fork release pin came out very easily (thank goodness).
Just to note:
I only needed to pull both drive shafts out of gearbox and tie them back out of the way instead of removing altogether
Superb. Went without a hitch and clutch is now ten times lighter and without any grabbing or juddering. Left knee will survive another few hundred thousand miles.
Cheers!