It basically gives them a more realistic look and lights them up by adding lighting fixtures so that the interiors look well lit. This mod is focused on the interiors of the buildings, caves and vaults. Best Fallout Overhaul Mods Interior Lighting Overhaul If you are a bit bored of the vanilla Fallout 4 and are looking for a new and unique experience, these mods are just what you need! Keep reading to find the best overhaul mods in Fallout: New Vegas.