catch 22. if you could see the PCIe connector, you could remove
the card. but, to see the connector, you ALMOST need to
remove the motherboard from the case.
i haven't studied the clip, but i know what you mean, you
sort of have to "jimmy" the card to remove it, even with AGP.
if you could look at someone else' A8N5X, or any motherboard
with a similar PCIe connector, you could manipulate the broken
plastic piece so it'll let the card go loose.
a dentist's mirror (good thing to have in a toolbox), or some other
small-mirror-held-at-an-angle kind of tool would be helpful.