Finally I 3D printed a mount for a slim DVD drive, mounted a USB/SD Card front pannel on the alu profiles and a 3D printed fixture and mounted the front plane on some wood spacers and applied an old Apple sticker :-)

The final benchmark results are really nice and the only noiseI I spotted was from my (old) monitor when I did not turn off the sound card :-) Initial test over 19.000 points in Cinebench R23 and also the stability test is only minor points below 19.000.