yep. all from your headlight switch
well your instrument lights are controlled by a reostat. (dimmer) but do they turn on less either your running lights or headlights are on? no. they get power from the same place your headlights do.
It's classic symptoms of faulty headlight switch. check your local junkyards. see if this link can yield anything
http://car-part.com/ just a junk yard database. check Pullapart.com
Oh and while replacing your switch be careful of that little spring. its a pain.
I feel down about giving you bad news. Wish I could help more buddy. good luck.