Specific character of a cell to display as specific number on another cell

Hi,

Need help with the following:

Cell 1: ABC1M123
Cell 2: DEF2T456
Cell 3: GHI3Y789

The 4th characters (1, 2, 3) equals to this: 1=25, 2=47, 3=69.
I need these values displayed in a separate column.

Cheers