Many years ago I faced this problem and made my own bracket, cut and folded up from very thin aluminium sheet. Might have been 1.6mm or maybe even one size thinner. That way I could cut its mounting holes so the radio would mount exactly flush. I also spent time working on the clip-on bezel you always get with radios, shaving it down so it fit inside the console cutout and filled the gap around the faceplate. Also, fearing the aluminium would be too weak not to sag, I glued a block of polyurethane foam on top of the cubbyhole below to absorb vibration and support the back of the radio.
That worked so well that I salvaged it from my old car and fitted it in my next one. Replacing radios over the years has meant a bit of time shaving down new bezels but it bugs me to have a radio that sticks out of the dash when it doesn’t need to. I recognise that’s a bit OCD. 