i want to buy new door speakers and mount them in the panel somehow, or build some type of little box on the panel to mount them in. can anyone give me some suggestions on a good size speaker to do this with, types of materials and anything else i will need to know please.
You dont want to enclose a door speaker. Theyre designed to be used in infinite baffle (big big enclosure for a small speaker basically your door.) If youre looking for ideas look in the interior forum at the How-to FG Your Door Panel Sticky. Theres a pretty good section about mounting the speakers onto the outside of the door panel. I would suggest mounting the speaker directly to the plastic. It will separate the speaker from the door unless you build up something that connects the door panel and the door so the speaker can utilize it properly.