No Kev, you right
i retract that advice , is was a joke but it could be taken the wrong way
sorry Harry i should think the cleaning shoul work ok, sometimes though some stains can be a bit 0f a buggery
and a poultice may be neededif that does not work then as a last resort light sand the offending surface unless its very deep .. and the material will allow with out further damage
Keep smiling