Dim lights in dash

IF you would rather go ahead and throw a new headlight switch at it...
Here's a tip, The new headlight switch will have an extra male space connection that is only used for a chassis ground path where the switch is mounted in plastic ( other models ).
Ignoring the fact that your panel is pot metal and adding a ground wire from that supplied terminal to a good ground location can work like magic for everything about the panel ( except for the park brake lamp of course ).