When trying to reassemble the drive shaft after pulling it out for what ever reason.
Fit the 6202 bearing to the cluct side of the shaft 1st.
Fit in in the hole.
Fit all the clutch wheel and stuff on.
Put the bucking ball and pin in the other side and press it in with the drive sprocket cover. The above will allow you to Tighten the flower nut.
Then you will get the bearing in on the drive sprocket side easily enough and the woodruff key will get in a piece of cake.
The reason why you'll have a hard time trying to just slap it together is the stoopid clutch spring will keep the driv sprocket side bearing from seating in all the way the spring needs to be depressed..
I'm abit slow it took me like 30min to figure that little bugger out.