Use a bit about half way between the size of the hole and the outer diameter of the rivet and just drill through the head of the rivet. Go slow so you don't go too far, you most likely won't damage the clip. Once you have done that the clip will just pull out of the hatch. GL.
Daniel, Previous car's: Grey 85 GT, Black 93 5.0 LX Hatch, White 85 GT w/T-tops. Current car: 2006 Freestyle. As funds allow will be getting a 90 or 91 5.0 LX Coupe and then will do a T-top conversion to it.