Thanks! It was fun to set things up.
One feed has:
Milwaukee Tower 119.100
Milwaukee Tower (Backup) 118.475
The other uses:
Milwaukee Approach (East) 118.000
Milwaukee Approach (West) 126.500
Milwaukee Approach/Departure Overflow 127.850
Milwaukee Departure (East) 119.650
Milwaukee Departure (West) 125.350
I'd like to add ground at some point, but I don't have very good reception as things are right now.