While my advice is not as detailed as Scott's, I do have something to add.

1)  Don't drill holes in fiberglass -- make an aluminum insert and mount the
insert to the fiberglass frame.  It's much easier to work with the aluminum,
and much less painful to throw away when you screw up your first attempt.

2)  As you complete the second attempt, you will discover that the $250 you
saved by cutting the holes yourself was not a good bargain.  The holes are less
clean, especially those funky ones like the ignition switch hole, the time
involved was hideous, and you spent $100 anyway on the instrument hole punch.

If I had to do it over again, I would avail myself of the services where they
lay out a panel in Autocad (or equivalent) and laser-cut it for you.  And I'm
reasonably thrifty, too!  There are several vendors who will do this and it
would be money well spent.

- Rob Wolf
LNC2 70%