I called the GM dealership near me and was told they don’t know the bulb size that I would have to buy a new cluster and hvac control? Seems odd no part store can tell me either. I know the hvac bulbs have to be soldered in but the cluster bulbs look like they just pop in and out. Anyone know the bulb size??

I seem to recall someone here replacing "bulbs" on something similar within the last year. I can't seen to find it though. I think your best bet would be to un-solder one to figure out what it is.

. . . or: See if FLSpeedo.com will take care of it for you. I've sent them a few clusters and they are excellent! One time they had a cluster for a friend'* 2004 Tahoe out, all stepper motors replaced, broken lens replaced, boxed back up, and ready to return to me before I got the [your package arrived] notice!

Pull the cluster and pop out a bulb. I believe they are marked .