The quick answer to my question is YES it will. I asked this on another forum last spring, but no feedback lead me to plough my own furrow.
So having put up with the Knock Knock of the old clutch, I finally did some research on a Kawasaki parts site & bought a secondhand 250R clutch basket & hey presto it fits, now the down side is I assumed Kawasaki would only change the basket backing plate to the spring damped one like most bikes have. But they changed the inner basket & the all the plates too ! I asume its a cutback version of a ZX6R with less plates, so I need a whole clutch, which is on order along with a cover gasket & site glass which for some reason cracked !
So if you want to lose that knocking noise from worn clutch bushes that sounds like the big ends are gone, just replace the whole clutch with a 2007-2012 EX250R one
I'll update this when I'm finished.