JR, I have had various, similar kinds of trouble with the instrument panel in my 1993 LS400 over the years (I still have it and love it). First, DO NOT take this problem to any dealer or another garage, even a Lexus specialty garage. Enormous waste of $$$. Around the country there are lots of businesses that specialize in repairing instrument panels and some of them actually know their stuff.
Other people may have their favorites, but the series of problems I experienced over the years allowed me to weed out some of the bad "instrument panel" repair shops and find a reliable one. By far, the best, cheapest and most reliable outfit is BBA Remanufacturing Inc., 300 Miles Standish Blvd., Taunton, MA, Ph: 1-866-573-2740. You can pull out the instrument panel yourself with remarkably ease (granted, doing it five times increased my skill.) BBA will send, maybe email, you instructions if you need them. Basically, you will remove a couple of small paned sections, starting with the one around your car key insert, then unscrew 3 Phillips head screws you can feel (but not see) along the top of the panel itself, then unplug a couple of small connectors from the plastic front - these are fussy but each has a place where a small tool will release the locking clip and then you can gently slide them apart with your fingers or wiggle something between them to pry them apart and then slide out the front part and put it aside (in a protective box or something). Next you will probably have to start sliding the instrument panel itself out and wiggle your hand behind it to unplug three larger connector sections from the rear of the panel itself - this will be challenging but if you can commandeer a small child to reach behind and aid him or her by unlocling the clip, usually in the centerof the connector, with a small pry tool, they will eventuall come free and then the panel can be wiggled out - it helps to have set your steering column to its lowest point - I started out removing the cover to the steering column then later discovered it wasn't necessary. Once the panel is in your lap, BBA will send you a UPS address label for you to paste on a box in which you have carefully, with lots of cushioning, packed the panel. UPS will pick up the next day and in about 10 days or 2 weeks, your panel will be returned to you for re-installation in roughly the reverse order of actions described above. They will charge between $200 and $300 depending on how many problems you have to fix. Shipping costs - both ways - may total $50, probably less. And they give you a guarantee!!! A real one! Mine had more problems about a year after the first fix (by BBA, I don't want to think about the three earlier (one of them 10 times more expensive), stupid, wasted efforts), so I called them and they sent me a shipping label, I sent it to them and it was returned completely fixed in ten days WITHOUT ANY cost to me - not even for shipping! Please let me know if this works for you. David