A method of installing a lightning protection system in a wind turbine blade with a first blade wall formed on a first blade mold, a second blade wall formed on a second blade mold, and a blade cavity formed when the first blade wall is secured to the second blade wall, the lightning protection system including a first socket with a first bottom wall, a second socket with a second bottom wall, a first receptor plug, a second receptor plug, a first receptor element, and a second receptor element, the method comprising: placing the first bottom wall of the first socket on the first blade mold; forming the first blade wall on the first blade mold so that the first blade wall is formed around, and at least partly includes, the first socket; removing at least part of the first bottom wall of the first socket to provide a first opening through the first blade wall via the first socket; securing the first receptor plug to the first socket with the first receptor plug at least partly disposed on an interior side of the first blade wall; temporarily securing the second receptor plug to the interior side of the first blade wall; placing the second bottom wall of the second socket on the second blade mold; forming the second blade wall on the second blade mold so that the second blade wall is formed around, and at least partly includes, the second socket; joining the first blade wall to the second blade wall to form the blade cavity; removing at least part of the second bottom wall of the second socket to provide a second opening through the second blade wall via the second socket; after removing the at least part of the second bottom wall, accessing the second receptor plug via the second opening to remove the second receptor plug from the first blade wall and secure the second receptor plug to the second socket; securing the first receptor element to the first receptor plug via the first opening; and securing the second receptor element to the second receptor plug via the second opening. placing the first bottom wall of the first socket on the first blade mold; forming the first blade wall on the first blade mold so that the first blade wall is formed around, and at least partly includes, the first socket; removing at least part of the first bottom wall of the first socket to provide a first opening through the first blade wall via the first socket; securing the first receptor plug to the first socket with the first receptor plug at least partly disposed on an interior side of the first blade wall; temporarily securing the second receptor plug to the interior side of the first blade wall; placing the second bottom wall of the second socket on the second blade mold; forming the second blade wall on the second blade mold so that the second blade wall is formed around, and at least partly includes, the second socket; joining the first blade wall to the second blade wall to form the blade cavity; removing at least part of the second bottom wall of the second socket to provide a second opening through the second blade wall via the second socket; after removing the at least part of the second bottom wall, accessing the second receptor plug via the second opening to remove the second receptor plug from the first blade wall and secure the second receptor plug to the second socket; securing the first receptor element to the first receptor plug via the first opening; and securing the second receptor element to the second receptor plug via the second opening.