Here are some heads I picked up recently - I was told that they were factory mods, but I don't know the full story. Whatever they are, it should be an interesting exercise to run them. If anyone could shed some light on them it would be appreciated.

http://farm4.static.flickr.com/3239/2332594886_f1fe464a9d.jpg?v=0

http://farm3.static.flickr.com/2339/2332594906_8980ddf43f.jpg?v=0

http://farm3.static.flickr.com/2216/2331768283_3c863780fb.jpg?v=0

http://farm3.static.flickr.com/2005/2331768377_285f0c8235.jpg?v=0

http://farm3.static.flickr.com/2202/2331768405_b86f824886.jpg?v=0

http://farm3.static.flickr.com/2128/2331768473_f862db37e6.jpg?v=0

http://farm4.static.flickr.com/3048/2332594808_ab0ce4afeb.jpg?v=0