Change the pants colour of a Mii

from wiili.org:

 

David Hawley has put up some information on how to change the pants color of a Mii to gold or blue using a hex editor. There are some caveats. Altering the pants color of a Mii will change its' status to 'Special' or 'Foreign', thus creating restrictions on it. The gold and blue color changes do not show during game play.