I dont know if this goes here...but why not....this is on ebay.....
Silverado SS engine on ebay (http://cgi.ebay.com/ebaymotors/Chevy-Silverado-SS-engine-change-over-swap_W0QQitemZ8022782799QQcategoryZ33615QQssPageNa meZWDVWQQrdZ1QQcmdZViewItem)

4l80e and 2wd on a 03 ss. Thats strange. not a bad price for a literaly turn key job.