yeah its easy bro - clutch cover off and some minor dismantling will reveal the other end of the shaft which you can just pull through and then slide a fresh one in its place. I recommend a fresh oil seal too. Its about four years since i changed mine so i cant remember any finer details for you but i just remember it being much easier than i expected.

I got all the parts i needed off tyga and Matt wrote me a list of parts needed for a re-build and all the oil seals worth changing whilst i was at it;

Crankshaft x 1
Piston x 2
Piston Rings x 2
Piston Pin x 2
Piston Circlip x 4
Gasket, Cylinder x 2
Gasket, Head x 2
Gasket, Clutch Cover x 2
RC valve seal x 2
RC Valve Shaft E Clip x 2
Seal, Crank Left x 1
Seal, Crank Right x 1
Seal, Countershaft x 1
Seal, Gear Change Shaft x 1
Seal, clutch shaft actuator x 1
Seal, Kickstart x 1

The list maybe useful to you in future.
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