Hi - I have a full sized SMP Titanium 2231.50 which unfortunately has a discoloured dial. I was thinking of changing it and came across a dial for the SMP 2230.50.00. Otto Frei says that this 2230.50.00 dial has a diameter of 30.5mm. Can anyone advise if I can use this for my 2231.50? Many thanks for your help!!