The mesh grill part is like pressure fit, maybe with a dab of goo or something.
I don't remember if I pushed it from the backside to pop it or if I used my eyeglass flathead on it to pry it out from the front.
I did take pics though:
It fits in this little channel:
Here is a shot of one out:
Here is a closeup of the side view:
Just to complete the set here is a shot from the backside of the door panel:
Them rivets must hold in that plastic grill or something else, they have no connection to the mesh grill itself.
I grabbed a whole used door panel off someone just to have a spare speaker grill.
The price was FREE if you come take it, so how could I refuse. :P