Many thanks - I genuinely appreciate your advice and for taking the time to help me. I’ll definitely take the approach you suggest as I really have no experience or expertise in repairs!
Afraid I do have the collector bug though so perhaps I should obtain a cheap project to make mistakes and learn some basics - I have a nice Gruen, Bulova and Vostok so far but I’ll certainly pass these to the experts for any future issues (touch wood none so far!).
Much appreciated,
Joseph