Some samples of GIMP mods

original tailights
132_zpseb6fc5b5.jpg photo by scuba33063 | Photobucket

gray tint
132a_zps5052cf96.jpg photo by scuba33063 | Photobucket

red tint
132b_zps650d59bb.jpg photo by scuba33063 | Photobucket

chrome painted black
132c_zps7bccf82a.jpg photo by scuba33063 | Photobucket

original window tint
PC090121a1_zpsdcb30cfb.jpg photo by scuba33063 | Photobucket

gold reflective windows
PC090121a1au_zps8e2436a9.jpg photo by scuba33063 | Photobucket

there is a photoshop plugin that works with GIMP called adjust, it has a button called "I feel lucky"

PC090121a1A_zpsb6006126.jpg photo by scuba33063 | Photobucket