I wanted to know how di I remove the Instument panel on my 2003 Lexus GS 300 the lights seem to be dim and I wanted to check the bulbs before replacing the dimmer switch

It's quite common as these age that the back lit display on the combination meter to go dim.
It will need to be sent out for refurbish. The surround bezel should have 2 screws above the cluster and the rest pops out. (4 clips hold it in)
The 4 screws should hold in the cluster with several connectors behind it.

There should be something helpful in here to get you started. Step 12 & 13.
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