The first post should outline the project.. Car, hardware, software, application (dvd, mp3, gps.. etc..) Since the project will most likely be evolving this will probably be edited often.
as for the name of the thread "mp3Car installs" would work I think.. or that could be the main title and you could have sub forums "completed installs" and "works in progress" Unless you want to keep 1 thread per user and just have that thread get updated.
Most likely It will not remain as regulated as you would like since the forum is realy open to any kind of posting. There will ineveitably be questions asked as a new thread, etc..
Maybe we should setup some new sort of example car page system that is a standard format. The individual users would be able to pick a color scheme, title graphic, and post photos with descriptions, but the rest of the site will be preformated. Any way that's my ideas for now