Thanks Gadge,
For now I'll take it that this one is a '61 model. Had a crack at starting it last night and found the blade plate was loose. Tightened it up and tried again, It kicked but then the blade plate and boss fell off (Not really sure why it fell off as there is no damage to the thread). It's missing the key. No damage to the keyway just no key anywhere to be seen. Looks the same size as a briggs flywheel key so I'll try one on the weekend and see how it goes.
Pete.
