Looking for an Assembly Manual

What is the best, most detailed, assembly manual for the 72 Duster. I have both of the 72 Plymouth Chassis and Body service manuals and I'm not impressed. I also have a Haynes manual for general reference. I'm trying to go back to stock and some things are missing from my car. For example, the insulator pad above the fuel tank. I had no idea what it even looked like until I did a search on this forum. Is there something that would show me a part like that with having to search every corner of the web?