Originally Posted by Ludford
Tried that, pushed it all the way in by hand but the wheel still refuses to turn.
Hmmmm, it sounds like the clutch is not disengaging. Make certain it is assembled properly. Try this: Remove the clutch plate (3 screws), pull out the long metal piece in the middle of the engine sprocket, make sure that the clutch baring (small round steel marble) is in the hole, can you see it in there? make sure the clutch lever is pointed toward the back of the bike, now reassemble.
I don't see how the engine could be seized if you got the chain on the engine sprocket.