I figured it out.
First, you want to roll the brass U trim outward from the top edge, while pushing up on it from below. I found a putty knife works well for this, something narrow will dent the wood. You need to lift it off those tabs along the top the retainers.
Next, slide the outside of the retainer mechanism to the right, then fold the retainer outward from the slots behind (they fold in the center). There are two retainers, left and right of the CRT center.
Be ready to catch the safety glass when you remove that second retainer. Mine about fell forward into my lap before I realized it was moving.
The bottom trim looks to be the same U channel as the top, I have not figured out how it's retained. It's holding mechanism seems different than the top.