Note: This procedure involves editing a game file;
create a backup copy of the file before proceeding. Reach the
end of mission screen with the customize, quit, and continue options.
Press [Alt] + [Tab] to return to Windows. Use Windows
Explorer to enter the "Variant" sub-directory in the
game directory. The files in this directory represent various
vehicles in the game. A text editor can be used to view the contents.
After selecting a new vehicle from one of the "Variant"
files, copy that file into the main game directory. Delete the
"User" file in the main game directory, then rename
the copied "Variant" file to "User". Press
[Alt] + [Tab] to resume game play with the new vehicle.