Partway there- - - - - -a couple of old geezers can still turn wrenches, even if we can't beat the flat rate manual time any more! Archie and I got the cylinder head off today, and it's definitely got a blown gasket- - - - -about half an inch missing between cylinders 2 and 3. The head followed me home, where it will get magnafluxed, checked for warp, the valve guides fitted with bronze liners, and possibly get some new valves. That should make it good to go for another 50+ years, when it will most likely be somebody else's problem!
Jerry