If the center pin on yours pushes in to allow the entire retainer to be pried out, then something like this tool I made 20 years ago would be ideal for what you're trying to do.
I turned this piece of 1” plastic on a lathe to allow the center pin on the trim retainer to be pushed in only enough to release the retainer’s hold in the door panel and allow it to be pried out.
My self and another mechanic came up with this tool when we were working on early design Chrysler 300’s and Dodge Chargers in the Chrysler Engineering Body Hardware Lab.
The problem this tool was designed to solve was that it was very easy to push the center pin in too far and lose the center pin inside the door.
When you are working on preproduction vehicles, replacement widgets may not be available.
This shows the retainer on the left with the pin pushed in to allow the retainer to be pried out.
The retainer on the right is how it would look with the pin seated flush, locking the retainer in place
This pic shows a bit more detail of the working end of the tool
It also shows a cross section of a retainer with the pin proud of the retainer face (left) and ready to be reinstalled.
The retainer on the right shows the pin pushed thru allowing for for retainer removal.
Hope this helps.
Honestly you can carefully push the center pin in with a punch (don’t go too far) and be just fine.
However, since this is GJ making or acquiring a new tool is encouraged.