All good points.

I am assured by the owner that the engine was not moved while the head was off (But then I have often found that owners wont admit to things they think might cost them more money! )

The point about crank pully slippage is also interesting however since the crank wont turn through TDC with the camshaft at TDC (Or at least as far as I can tell) there must be something else going on.

When I get back to it I will try to check these things further.