anyone help, oil seal behind drive sprocket has started to leak , looks like wear and tear does anyone know if seal can be changed from front with transfer shaft in place or does the caseing have to come off , if i remove caseing does it all just fall apart , not too sure of what i am doing but if its only leavering one out and drifting one back on with a socket then great , but with my luck it will be a garage job:dunno