Have you removed the neutral cut-out switch form the underside of the clutch lever assy ? Winding the cable adjuster in as far as it will go will help give a little more cable slack. If you need a bit more give in the cable, grab the throwout lever on the engine itself with a pair of pliers and rotate it clockwise a little while pulling the clutch lever out at the same time.
Edit - oops, you got in just before me !