Electroluminescent problems

[IndyImp62@xxxxxxx]

Hello Imperialists:

The dash went dark this evening on my 62 conv.   I have replaced 1 power pack 
and repaired another during my 2 years of owning this car.  Recently I have 
had to work the headlight switch a couple of times to get the dash to light.  
This evening while driving this did not work.

Any suggestions? Is there a way to troubleshoot whether it is a ground, 
headlight switch, or power pack.  That pack is a devil to get out if not the 
actual problem. 

thank you,
Steve
62 & 65 conv.