You'll have to clear out one of the two sets, and then change the other set. Once you change the other set, you can then re-record the set you cleared.
To clear out a keyboard shortcut, double-click the shortcut, then click the 'X' to delete the current shortcut. You'll see that it is cleared (empty) in the list. Do this for all of the Set Photo Color Class entries.
Then record the Set Photo Rating ones by double-clicking each of them and recording Ctrl-number (where 'number' is the number you want to use--the same number as it currently has).
Then record the Set Photo Color class entries to use just the number keys.
Do this a second time for the Preview section (as outlined in the last screenshot above).
HTH,
-Kirk