Got my dash back tonight.
To save people a bunch of time for anyone that wants to try this...
DO NOT USE Duraglass or fiberglass resin and mat to shave the channel around the dash piece. It will not adhere to the plastic and eventually you will get cracks.
Ended up having to grind out all that crap and used a slow curing epoxy to get it nice. I'm talking it takes 24 hours to tack up but its rock hard and adheres well to ABS. Worth it in the end. I honestly don't see how Soundman gets away with using the products he uses to modify his dashes. I'm guessing a lot of them crack and look like crap.
It was painted about 5 hours ago so I'm not even going to mess with it until Friday. My new iPad isn't supposed to show up until tomorrow or Friday anyways.