A vehicle lamp installation method includes, among other things, engaging both a mounting bracket and an outer panel of a vehicle with an alignment fixture that locates the mounting bracket relative to the outer panel in a mounting position. The method further includes securing the mounting bracket to a body structure of the vehicle when the mounting bracket is in the mounting position. A vehicle assembly includes, among other things, a body structure of a vehicle, a mounting bracket secured to the body structure in a mounting position, and an outer panel secured to the body structure. The mounting bracket is located in the mounting position relative to the outer panel using an alignment fixture that engages with both the outer panel and the mounting bracket.