Well, we've had a look at the head gasket I took off about a month ago and decided that the block must be warped - it's black between the pots on the side that was next to the block.
Answer - out with the engine and do a rebuild. Get the block skimmed then put it back together with new bits and pieces.
BUT - in the meantime, we're doing a bit of an experiment. Got hold of some stuff called Seal-Up manufactured by CarGo. $10 for a 250 ml bottle. Sort of liquid glass stuff that hardens and forms a seal where the trouble is.
Will let you know how it goes. (Still pissed off though

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