The topic that never dies!
Ahem, anyway, I found a link to a torrent called Invisible Girl Watermelon. The process is shown fairly early on in the video. Unfortunately, it is not translated, but the action is understandable. It is a amture video, so if you are under 18, don't download and watch it!
http://www.akiba-online.com/showthre...ht=*invisible*