Before removing the dash to try fibre-glass, try a local repair with car-bond (e.g. sikaflex)
http://cgi.ebay.co.uk/SIKAFLEX-221-B...1%7C240%3A1318
This is not the same as silicon sealant (which just fills holes), this is a very good adhesive and sets like hard black rubber.
If you can find a way to keep the dash flat and level either side of the crack while this sets, it will hold it and also fill any holes (trim it level with a sharp blade when it's part set).
Do it carefully and the repair will be very inconspicuous.
BTW, what are you studying?
John