we put the ats two-piece 03 manifold on some trucks 2 weeks ago, much more responsive than stock, slightly lower EGTs at cruising. easy install, but drilling for the EGT probe was a pain. found another one on sale on ebay as well.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2452275274
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2452275274