They are push clips, I never found a way to get it apart without breaking a few.

 

I got a hold of the OEM clips from my Ford dealership. They had to order them. I cannot, for the life of me, remember what the part number was though .

When I replaced them, the panel was still loose. The mounting holes in the door itself must have been worn down. If you can find aftermarket clips that are a bit bigger than OEM, it'll probably work better.

 

The part number is
FML-$$$$$-666

 

I don't know what the part looks like but I'd just go to the dealer, they will be able to get them. I worked for an automotive fastener company and we were still producing parts form 40 year old dies.

 

What he said.

They were definitely still in production when I got them about a year ago.

 

I bought several packs from a dealer a few years ago because my driver side door panel came loose. After several times stabbing my fingers and other cuts I bought all new ones and installed them, don't bother trying to take them apart.
Dealer # W704958-S300, pack of 4.
Good Luck