Thank you Pottz and GeorgeWest. I think I can shim it cleanly so it will match. Started to get some pieces ready to do so when I had a minor kickback as one of the smaller pieces I was using caught. Wasn't major but decided it was a good stopping point to clean up the shop and decide how best to fill the gap.
One thing that really helped with the bevel cuts (I think that's the right terminology for 45s on an edge?) was to take a sled I wasn't using much and adjust it for bevels. The right panel can slide over (after I adjusted the opening for the knob). Worked great and my joints seem tight. Hopefully will give a good glueup.
