How to remove plastic door latch?

The black plastic latch that keeps the door of my new (old?) '72 overlander open has broken. There are several other identical latches, e.g. on the back bumper, that I'm not going to use, and so would like to remove for replacement. The challange is that I cannot figure out how to remove the sliding part (without breaking it) so that I can get at the mounting rivets on the base part.



Anyone know the magic?



Thanks!