I found that one out (cutting off those tabs on the panel) during my installation. I agonized for a while because in order to silkscreen your panel you have to remove those tabs...there's no way to get a screen to lay flat with them interfering. It was tough to get myself to cut them off initially, and then I realized that there's no reason you can't rivet in angle like that, and it would
be better in the end because now the panel is removable as you have shown.
Thanks for posting great pictures. Hopefully it will make it easier on people who were in my shoes...living in fear of what was going to go wrong if they cut those tabs off.