PS. Forgot to add BUT if it is the body that is a bit skew wiff, then you might have to rotate the gas cylinder accordingly to allow the locating prong to locate into the slot in the gas regulator. We had a special alignment gauge for this when we were fitting new gas cylinders. But shouldn't be a big problem and fitting a new slightly oversize taper pin should solve the 'problem' - if there is a problem. There's plenty of meat in that area