Plastic Panel Please Help

     Hi there I am doing some glassing on my rear window panel is all one piece on my car all the way to the floor.  What I am trying to do is recess an amp into the panel just below the window. To paint a better picture, I cut the panel out and stretched material over the opening to house the amp I made an MDF box and attached it to the vehicle.  I reinstalled the panel and the outline of the box shows through and resined, o k.  Now here is where I ran into some problems.....How do i get the resin/fiberglass to stick to the panel?  Should I just glass the whole panel like gta94integra did to prevent warping/cracking of the bondo?  How many layers of glass?  If so should I scuff the panel, what grit sand paper? Should I start over or is there a fix? I looks ok so far except it is peeling away from the plastic in spots.........Sorry for the long post and all the questions any help would be great it is very frustrating as of now but I'm hanging in there.Thanks  -CarStereoNut--Neekos-

To make glass stick to anything better scuff it up with some low grit sand paper. to make it stick better and to go thru cloth to stick to the MDF ring or whatever ur getting it to stick to add a little acetone to thin it out. hope that helps somedream it, build it, fiberglass it

sounds like you just need to put on a few thin layers of glass unless you plan on being extrmely ruff with the back dash

The absolutely best way to get a custom fiberglass added piece to stick to an ABS panel is to drill some small holes into the ABS behind where you are doing the glassing. And when you fiberglass, allow some of the resin to go through to the back side, and to add some matting back there, this basically makes fiberglass "rivits" and makes the fiberglass stay molded against the ABS. Good luck with your install.