I had the same problem with a 94 LS 400. You are speaking of the instrument lights right? I found a guy in Canada that will repair the problem. You send him your cluster, it is easy to remove. He repairs it and sends it back. The cost was about $150 U.S. It fixed the problem and it worked great. His company name is Mr. Whizard. You can find him on the internet at www.mrwhizard.com . I would recomend him to all for this problem or any instrument cluster issue.
I hope this helps.