Hi Beakerstoyz! Is that from Ron's Black car? You can repair this with this for "Med" reconstruction:
http://www.canadiantire.ca/en/pdp/bondo ... vc2C4f2bmg, heavy rebuilding I would use something like this:
http://www.canadiantire.ca/en/pdp/bondo ... vc24of2bmg. These are both the same material that Clyde has pointed out just different length strands in the resin, for finishing work, use Bondo or spot putty as required. The only thing that stands out for concerns is surface prep, the rougher the better in my experience, rough it up with something like a 40 grit on your 4 or 5" grinder and mix small amounts and build up slowly, so use caution large amounts with lots of "Hardener" will make lots of heat and that isn't good for your 40 year old spoiler, and will affect adhesion. Plus some of these materials can be a
bear to sand, so again small and sculpt as you go, into the early "green" stages once it starts to "Go-Off" more than a little it is time to stop until hard. If you haven't done much of this kind of work practice on some scrap, this isn't hard just a little different than something's you may expect. That is a hard to find part, so no shame in a practice run! You will do fine. Harry
I'm not a hoarder I'm a preservationist 78 Monza Spyder (~Soon(ish +/- I guess) To Be 2+2 with Spoilers)