Definitely now erring on the side of 'leave well alone'.
My local garage are no longer doing 'old school' work, but managed to find a Heritage specialist locally who's going to whip the engine out (he's recently been working on a Lotus Elan, and a Westfield 7, so has experience of the engine/gearbox, and is a fast ford specialist). Going to cost me about £400, but that's not too bad. Will get him to do a visual on the clutch to see if that needs replacing while the engine is out. Downside is he's really busy, so may be a fortnight before he can get on to it. Always consider that a good sign though!
