I've never been particularly gifted with things of this sort. I've never
worked
with fiberglass before, and moreover, I'm worried about the damage I'd do to
my
car.

Seriously man, fiberglassing is not as difficult as you may think. I am about
the most un crafty person in the world, but recently I managed to build a
pretty decent sealed enclosure for my sub that tucks in behind the wheel well
in my truck. It took me about 5 days of working when I had some spare time,
but it really wasn't THAT difficult, and its great to have done every single
bit of my install myself.

Nick