I have the Paolo Marasa 330/P4 book. There are some engine bay pics and several detailed exterior/interior (skin on) pics of the restored P4. Unfortunately there aren't any frame/chassis pics. I have about 50 general jpgs. and the old large Shell Oil cutaway drawing (also small version in jpg form). I can't scan everything as I do have a life but I can send the jpgs and/or scan a few detailed pics if you have a specific need.
In case you hadn't guessed the 330/P4 is one of my all time favorites.