Video shows how to take apart your HTC ThunderBolt in time of need2
The reason why you need to be out of options before starting a do-it-yourself repair job is that opening up your HTC ThunderBolt will void the warranty on the LTE enabled smartphone. As long as you have the warranty in effect, or even if Verizon will exchange your broken handset for a CLNR model, there is no reason to attempt this.
Since the warranty on the HTC ThunderBolt still has some months to go, why not file this video somewhere where you can access it if the situation ever arises. And again, opening up your device should only be done as a last ditch effort.
source: YouTube (DirectFix) via AndroidandMe