Through the lens but you need to make a tool for ease of install. The tool is just a gum wrapper folded over the bulb and pinched between your fingers. This gives you a handle to hold the bulb. I was able to put mine in with out a tool but it took two try's and had to rethink the install.Rear license plate bulb out and dash lite is illuminated. Is it easier to access through the inside rear door panel or through the outside light lens? Do the rear door panel retainers just pull out or is there a tool?