what size are the light bulbs in the instrument gauge cluster on the dash.

For SAFEST results , call DEALER first , make sure they stock the needed bulbs , and bring the cluster in with you and match them up.Some bulbs can look and fit the same , but be different wattage and cause problems. Just a thought.

There's two different size bulbs in the gauge cluster if I remember correctly. The bulbs that illuminate the gauge cluser the burnt orange color are 168/192 bulbs. You can use an orange 168 bulb but it won't be exactly the same color as the stock bulbs. The stock ones are actually clear but they have an orange rubberish sock that is slid over the bulb to create the orange color. The only place you can get those at is the Lexus dealership but you have to specifically ask for them. You can reuse the ones from the existing bulbs that are bad but a word of caution: if the bulb has burnt out or is extremely old the rubber sock will not come off in one piece as it will most likely be fused to the bulb. I learned this the hard way. Just be careful when you try to slide it off and make sure the whole thing is loose before doing so. The other bulbs in the gauge cluster are Lexus/Toyota part # 90010-06039. These are the smaller bulbs and will come with the orange bulb covers and plastic mounting housing attached (BLUE). The larger 168 bulbs are seated in a BLACK plastic housing. Once you get the gauge cluster out and flip it over you should see the different colored housings where the bulbs mount.