Rocker box was tidied up with the wet n dry and plate glass method - came out pretty well, placed it back on the head- shockingly bad and still pivoting on a high point on the head and could get a 25 thou feeler gauge in the gap! Also discovered a high point on the head, appears to be on the face that separates the cylinders. The whole lot has gone of for refacing to a local engineer, had to knock the guides out which will need replacing. So with all those issues not a chance in hell of getting it oil tight.
Hopefully this will sort it once and for all- will keep you posted.