Door Panel Help

Hey yo.

Quick question that has me stumped. Ok, i just bought a door panel from a wreakers that is the same as my cars, and wanna play around with it before i attack the real ones. I am after that ultra clean, super smooth "Plastic" look, u can get from highly sanded and primed fibreglass, but i want it as a panel on the door panel to hold a speaker.  Just to try and make things a big more logical there is a picture of what i mean here....

See the black plastic inserts... particularly the long one at the back of the door and the speaker housing at the lower front of the door.  Now i am assuming that is fibreglass, but what i would love to know is, how do u attach the fibreglass to the door without making obvious screw holes, and how do u get the fibreglass in after u have vinyled the door, i assuming the fibreglass needs to be out to get a nice fit with the vinyl...

are there some sort of clips or something u can attach from the back to make the panels stay on? or is it suppost to be stuck on there from the start? any help would be hugely appreciated, and if u can't understand what the hell i am on about, please ask and i will try and explain better... i am really keen to get stuck into this door.

cheers, tomy j

The installer probably did the door one of two ways ( can't really tell from the picture ) but here goes:

1. The flames are fiberglass or vinyl and are attached via epoxy glue

2. The flames are underneather the door panel and the design was made into the door panel before it was finished to show through the black flames.