Recently rebuilt a 340 invader motor myself, and this was a nightmare. It took me a full 10 days to get it off, and I'm still scared the crank is going to explode randomly after how hard I had to pound on it with a mallet to get it to come off.
I broke two smaller pullers just trying at first, so bought a bigger one but it wouldn't fit. decided to take the crankcase apart before the flywheel, not knowing the stator plat was mounted with one screw in each half of the crankcase, so I broke the stator plate. I strongly feel like I never would have gotten that flywheel off had I not done that though.
Motor runs, and a got a used stator plate online soooo....