For as long as I've had my '98, the "flippable" emblem that covers the trunk lock cylinder has lived in the glove box. According the previous owner, it just "fell off".

I am unsure on how I'm supposed to go about re-attaching it. I assume the rivets holding the base plate have to be drilled out, but then how on Earth am I supposed to re-attach the thing?

 

I believe the cover part should swivel sidways and lock in place out of the way so you can insert the key. Then it releases when you insert and turn the key so the cover swings back into place. It looks like your cover has simply broken off. I think you'll need a whole new trunk piece with the swivel cover still attached. It will have to come from a parts car. You'll have to replace any drilled out rivets with new rivets or some kind of equivalent screws. To do the latter will require some creativity. I would look at the piece from the inside of the trunk and see what's visible and what you'll need to do to get at the back of it.

 

You'll need a new lock cover from a parts car. Here are 2 salvage yards you can check.

https://www.dvap.com/

http://www.ctcautoranch.com/

Actually, that looks nearly identical to the setup on my 71 98. Hopefully someone can confirm what years that lock cover can come from (maybe 71-76).

 

That's a shame since that one still has the plastic insert and it's in good shape. The service part didn't have it.

No biggie to drill out the rivets, remove the lock cover ornament and see what's going on behind there, then pop rivet it back in place- hopefully FIXED!