I just sent one out for repair two years ago for an '87. There have been some I was able to repair by resoldering intermittent connections but I couldn't solve this one. It was doing exactly what you described. The big authorized repair centers had just stopped repairing them because they said they could no longer get parts, but most of the time parts are not needed.
As a point of interest, a similar problem developed a month ago on this same car. This time they took it to one of the premier automotive electrical shops in my city. Two of my former students work there. One of them found an intermittent ground connection behind the dash that he believed was the cause this time of the dim display. Haven't heard from the owner so I have to assume it's still working.
The shop I sent the dash to two years ago is Advanced Auto Electronics, Inc. Their web site is aaellc. Com. Got very good service from them.
Thursday, August 16th, 2012 AT 4:04 AM