This is one sweet item. I had a nice link to it a year or so ago but it's dead now so here's what I was able to Google on it.
http://www.gm.com/company/gmability/safety/news_issues/releases/cts_041105.html
http://www.conceptcarz.com/vehicle/z11581/Cadillac_STS SAE 100/default.aspx
http://www.ultimatecarpage.com/frame.php?file=car.php&carnum=2300
http://www.worldcarfans.com/photos.cfm/photoid/3050411.001/country/acf/Cadillac/cadillac-sts-sae-100
http://www.gm.com/company/gmability/safety/news_issues/releases/cts_041105.html
http://www.conceptcarz.com/vehicle/z11581/Cadillac_STS SAE 100/default.aspx
http://www.ultimatecarpage.com/frame.php?file=car.php&carnum=2300
http://www.worldcarfans.com/photos.cfm/photoid/3050411.001/country/acf/Cadillac/cadillac-sts-sae-100