I have a sunpro tach, and im aware that the white wire is supposed to go to the dimmer switch.

Question is where on earth is the dimmer switch and how do i get at it?

 

the dimmer switch is your head light switch.
hook up to your dash lights.

 

You can tap into the grey wire behind the instrument panel or directly at the fuse box (INST LPS fuse), that's the wire you're looking for.

Hope this helps.
Lou

 

I'll try that as soon as it stops raining here.

 

Well, send some rain our way! We haven't had good rain in years. The lake is 30 ft down, you can WALK across it, which means that drinking water supppy is low and of course everything is dead (yellow grass all-year-'round).
The curse of Central Texas.

Let us know what you find and how it goes.
Lou