Looking for advice for a 1986 420sel. No dash lights/buzzer/licenseplate lights. Here is what Ive done:

1. I checked #11 fuse cleaned the contacts and changed it for a new one.
2. Just to check the bulbs I ran a 12v wire from the #11 fuse to the license plate lights - each light turned on.
3. Used that same wire, pulled the dash an was able to get instrument lights working just by applying it to the back of the adjustment knob - all the lights in the console and dash lit up and dim properly when you adjust the knob, so that seems to be working.
4. I also checked the grounds behind the dash and tightened them.

All the other components on that circuit seem to be working, i.e.: headlight washers and right tail light work fine. Any suggestions? Also, I read a post talking about the interior light relay and light control relay, anyone know where these are, could they be the culprit?