tail light/ stop light replacement on 2002 GMC Envoy

What is the bulb layout from left to right of the three light bulbs. i need to replace the right stop light bulb and I am working by myself so I neeb to know which bulb is which.

Asked by for the 2002 GMC Envoy
I think the brake light bulb is the one on the end of the socket that has two screw holes. A good way you can check it is to wedge a snow bush or similar between the brake pedal and the seat (with the engine off and transmission in park and parking brake set). This will turn on the brake lights so you can see them. These vehicles are common to need tail light sockets also. The bulb may not repair the problem. If you dont get it fixed, give us a call. We will check it out for you.