Worked on the new frame today. And VOILA! Success!
I assigned part of the work to my shop helper (my CNC) and let him do the work. I admit, I did stand around and watch him to make sure he was doing it correctly.
I used 3/4 inch Baltic Birch and planed it to .605 inch, which is the same thickness as the existing frame. A 3/4 inch router bit did the planing job. You might have noticed the blue painters tape under the work piece. I tried a method a You Tube video describes of using the tape and super glue to hold the work piece in place. It worked great!!!
I provided a link to the video below.
Then it was time to cut the frame.
The first file run was the one that drilled some mounting holes in the mirror cut out and the four corners of the work piece. I screwed the pieces in place and then continued with the rest of the cutting.
The next file cut out the waste area where the mirror will be visible and then continued with the next file which cut the dadoes for the mirror and the backing. When that job was done, I placed the mirror and the backing in their respective dadoes and they fit nicely. Kudos to the designer!
After the dry fit, I ran the cutout file and the job was complete.
After removing the frame from the work piece, I used the band saw to cut the tabs off and then trimmed the remaining part of the tabs with a flush trim bit mounted in the router in the router table. A little sanding and it is ready to finish.