If you youtube it, you can find instructions for the Katzkins as well. I would definitely go the Ebay route. I recently saved $220 bucks by doing my speaker and head unit install myself and learned a lot about how my interior is constructed. You can't beat saving money and learning about your car at the same time! $1200 is just way too much for a leather interior.
So you ended up replacing the HU...awesome bet it sounds way better than the skipper.