I attempted this one myself with one of my co workers (I work in a repair shop) and we found that at around 650º-700º Fahrenheit with a heat gun is when the circular glue holds in the black plastic shielding give out. So, use a normal desktop sized P2 flat blade and wedge it in the side of where a circular glue hold has popped and it should be able to walk down the side of the shielding with the aid of a secondary screw driver, which will cut the glue as you go if you're applying heat. Then when you get down to the keyboard, just use a dremel tool to grind the posts down, because f**k scraping each individual one; you'd be there for half an hour.
Hope my research helps.
Cheers,
The Mac Whisperer