here's a link to pics of my exhaust. 3-1/2" all the way to the bumper with hooker aero chamber mufflers and there is a clip of it running.
http://www.forabodiesonly.com/mopar/showthread.php?t=199600
http://www.fiberglassforums.com/
http://www.dragstuff.com/racing/Body/
try these links they maybe helpful. mght have to custom order or build it yourself by using your hood to make a mold