Something I've found provides a neat effect when doing gauges...
Paint your panel whatever the base color is...flat black, gray, whatever...then drybrush white over the instrument bezels to outline the increment marks and needles, etc. Then, with a very fine brush, apply a drop of India ink to the gauge face, just enough to fill the recess without covering the raised details. Let it dry and settle, then a drop of Future over the top. Once that's done, I'll drybrush some dark silver (Floquil Old Silver is my favorite) around the edges of the bezel. Works like a champ for me. The India ink seems to have the blackest finish I've ever seen with the proper sheen.
Jeff