Console

You can cover the MDF in painters tape and/or tin foil and use mold release and then glass on top of it.  Even with the foil or tape on the MDF you can still staple the fleece to it.  When it hardens, you can take the whole piece out of the car and take the MDF out of the fiberglassed piece if you wanted to.  Me personally, I would always leave it in as a support.  You can always make a chamber inside and paint that and add neon and a plexiglass or lexan outer window if you want to make it look nice. Plan, Research, Do

Ok, I didn't even think foil/release technique (D'oh). I'd like to leave it in too except for, when working in there I'd have some personal issues, and making additional compartments, boo, hiss. Ok, thanks for the info, I'll remember that when I get around to redoing my car's interior.1998 Monte Carlo w/

Eclipse CD8454

2xRockford 5.25" Power 2-way T152C

2xRockford 6"x9" Punch 3-way FRC4369

1xMemphis 16-MCH1300 5-channel

2xKicker 12" L5 Solobaric-2 Ohm

the last one i made when i took it out and beat it with a bat it didnt crack it was very solid and it didnt have any supports at all. I mean i hit that thing so hard ken griffey would have said damn... Nadda... so i think no supports would be ok

Yep, if you make it strong enough and don't want the MDF to stay inside, take it the heck out. Plan, Research, Do