To find the correct bulb numbers, you need to consult your owner's manual or an automotive parts store website (like AutoZone, Advance Auto Parts, or NAPA) and specify your exact Silverado model (1500, 2500, etc.) and trim level. You can also search online for "1995 Chevy Silverado brake light bulb replacement" along with your specific model.
The parts store websites usually have diagrams of the taillight assemblies to show you which bulb goes where.