You could start by painting the panels the full intensity black color and then carefully toning it back with a few dry brushing sessions using darker greys. This will keep the deeper reccesses of the panels black while creating enough of a contrast to be able to pick out the details of the panel with your eye.
You can also go with a wash technique. Paint the panel a mid grey tone and put repeated washes of thinned out black drawing ink over the panel until you have the look you want. If you thin the ink out enough, it should take multiple sessions to work up a full opacity with washes of it , so the crevices and deeper portions of the panel will get a fuller intensity of the wash color while the higher details will remain lighter.
Hope that helps