I've got the rear wheel off my 350G and am attempting to disassemble it. First up, the hub and, right this second, removing the sprocket. I've removed the four nuts which hold down the sprocket and removed the Giant Circlip and the Great Big Washer, however the sprocket does not want to move; or rather, it'll move a fraction of a millimeter rotationally and mayyyyybe as much as 1mm in the direction of the threaded ends ("up"? "off"? "in a pullward direction"?), but in both cases, the threaded ends all move with it. Is this just another case of 'soak things in various chemicals, heat them up, and hit them with hammers until they free up or you break something" ? If hammers, what should I (or should I not) be striking?