There is no simple answer because you have to take the riders physical condition and riding style into account. That said even though the article-method that Tom points out above is strictly against the KOPs method I think it gets you in the ballpark. Once you are close you can make small adjustments until it feels right to you. This would be after using the heel on the pedal method to set saddle height.

Bicycles are very adjustable, nothing is permanent, so adjust away until it feels right.

I just wanted to add that the saddle shape-size should not matter, if you ride the bike for a few minutes before adjustment your can will find its natural position. The method they use at bike shops now to measure your sit bone width helps a lot in finding the right size saddle, unfortunately vintage Brooks only come in one width.