The only way I know to do this is to manually change a file named "Main_CharacterStats.txt" in the Campaign Folder (i.e.: Homefront).
You should take note of your current stats and after installing the full game you place them here:
Starting Credits                                     := 200000
Base Attack Rating                                   := 5
Base Defense Rating                                  := 5
Base Negotiation                                     := 0
Base Hull Regeneration Rate Per Second               := 0.00
Base Armor Regeneration Rate Per Second              := 0.00 
Base Shields Regeneration Rate Per Second            := 1.00 
Base Energy Regeneration Rate Per Second             := 1.00 
Then you start a new Campaign (i.e.: Homefront) with all stats at the levels you specified.
Have fun.   
