A method for retrofitting a lighting system includes providing a lighting assembly with a screw-terminal-base connector disposed in a lamp housing. A power-supply conductive wire includes a second length coupling the screw-terminal-base connector to a transformer and a first length coupled to the transformer and coupleable to a power supply. The first and second lengths of the power-supply conductive wire are severed and the transformer is removed. The severed first and second lengths are spliced together. An Edison-base receptacle is mounted to the lamp housing. The second length of the power-supply conductive wire is electrically coupled to the Edison-base receptacle.