WOLF bench grinder type 8356 HELP !

Does anyone know the correct way to connect the 15amp power lead to this model please ? Some helpful soul has removed the input cable from my old twin head grinder. It has 8 possible connection 'poles' around a square block, numbered in pairs. Three are used for internal connections 9/5 has a brown lead, 11/7 is black and 4/16 is blue. 1/13 and 2/16 are inaccessible behind a metal plate. That leaves me with three options 6/10, 8/12 and 2/14. The earth point is on the casing.

So if you have a Wolf bench grinder model 8356 would you please help this old codger out and turn yours upside down and see which input wires connect to which pole PLEASE. At the moment all my attempts have only got the machine to 'hum' quietly.....I don't even recognize the tune ! :C