Clutches are going to be in stock very shortly. They have been discoed from GM for about 3-4 years now.
http://www.gbodyparts.com/product_info.php?products_id=1813&osCsid=8c537ddf965bf793fc116ea75ea6341a
http://www.gbodyparts.com/product_info.php?products_id=1813&osCsid=8c537ddf965bf793fc116ea75ea6341a