Thank you. That helps a lot. It was confusing me that the voltage taps were labeled but the main winding taps were not.It is apparent from the diagram you provided that the main winding taps share number identification with the voltage taps. This was also confusing me.
The main winding taps are currently brought out to the primary input terminals. Since it is setup for 240 I will need to remove them from the terminals and determine which is which. I can then install jumpers to wire the windings in series for 480. I am guessing I will need to retap since nameplate voltage is 460. I am assuming using voltage taps 1,2,7,8,13,14 would get me closer to 208 with a 480 input.
As of now this transformer is spare. I would like to rewire it so that I know it is ready if needed. Thanks for the help.