In my case I had to edit the MaxPettyOfficers and MaxOfficers in 3 places for it to work. I don't know which file has priority so I changed all of them. You have to be in port and out of the game or it will change back by itself.
I'm using Vista so your folder structure might be a little different.
C:\Users\<username>\Documents\SH4\data\cfg\SaveGam es\ActiveUserPlayerUnits.upc <-- edit this file
C:\Users\<username>\Documents\SH4\data\cfg\SaveGam es\game# folder\UPCInitial\ActiveUserPlayerUnits.upc <-- edit this file
C:\Users\<username>\Documents\SH4\data\cfg\UPCInit ial\ActiveUserPlayerUnits.upc <-- edit this file
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