To answer you both, this door was a great to start with. The lower door panel was a good base to build off of. I cut a ring to mount the 6.5" speaker into out of 3/4" MDF and screwed it into the plastic door panel using the long screws to angle the speaker where I wanted it to point. I then stretched fleece material over the speaker ring and secured it to the back of the panel with superglue a little at a time stretching it tight as i went. Then when the fleece is tight, mix the fiberglass resin and coat the fleece thouroughly letting it soak the fleece especially onto the speaker ring. Once this cures it will be hard and you can start laying fiberglass cloth into the build out and coating with resin until you get it about 1/4" thick all over the build out. once you have that complete I mixed more resin after cutting the cloth from the speaker opening and poured it into the opening and rolled the panel around coating the inside of the buildout with resin and letting it harden. After this cures try pressing on the build out and see if it is stiff enough not to bend and add cloth and resin to harden it up more. Then it just goes to sanding and smoothing the surface to where it needs to be to either paint or cover the panel.
I like doing this kind of work, very rewarding to build something from nothing. Try it you may like it too.
