This is my first mod for GTA so it may be a little bad. It is a simple skin that gives Claude green hair and a lot of lightning bolts over his body. Also, he has two USA flags on his cheeks.
1. Download the zip file and extract it.
2 Move "POWER TO AMERICA.BMP" to the skins folder (C:\Program Files\Rockstar Games\GTA3\skins or similar)
MORE INFO IN README.
PS. THE LIGHTNING BOLTS HAVE FAILED. SORRY ABOUT THAT.