Kits and methods and apparatus are provided for retrofitting a lamp for use with a modular lamp controller. In a representative embodiment, a kit includes a port connector, a first portion of a port adapter, a second portion of a port adapter, and a lock nut. The port connector is configured to accept a plug of the modular lamp controller. The first portion of a port adapter has a threaded section. The second portion of the port adapter has a threaded section. The first and second portions are configured to be placed in opposing relation about the port connector to securely surround the port connector while fitting into an opening within a fixture of the lamp. The lock nut screws onto the threaded sections of the first and second portions of the port adapter while placed in opposing relation surrounding the port connector to secure the port adapter and port connector within the opening.