Are the SIM cover screws captured or loose? That is, after removing the cover, can the screws fall out or they stay in place? As I loosened the screws they did not rise up, then stayed flush with the case. This suggests that they are captured, that the cover is stuck in place (with that often mentioned sealant?), and that by loosening the screws I may have stripped the case threads.
If the screws are not captured, then why didn't they rise up, even if the cover was stuck? How many screw turns does it take before the SIM cover can be removed?
BTW, after "loosening" the screws I did try prying the cover up with a knife blade. No luck.