If it's an original screen, or even one that's been in for a few years, you've got little chance of getting it out in one piece. Sierra's are shit for holding water around the screen - the "seal" around the edge isn't a seal, it's just a trim, but they get tired, allow water to seep in, and that sits under it around the edges of the screen. The screen ends up adsorbing the water and moisture in between it's two layers of glass, causing it to delaminate, which makes it very weak.

I can get them out with wire, but even then, trying to save the terminals on the bottom of the glass is very very hard, and most end up breaking the solder joint rendering it useless.