The light inside my tach no longer comes on. The 8-pin plug on the back of the tach doesn't want to pull out. And having removed the 3 screws in the back of the tach the black plastic, rear part of the tach doesn't want to separate. I hesitate to force these things because the lack of a light doesn't warrant the risk of breaking something. The tach works fine otherwise. Also, I don't even know if the lightbulb is accessed from the back or if you have to take the front glass off.