A ballast for a florescent or HID lamp includes a housing enclosing florescent or HID lamp ballast electronic components; a plurality of lead wire extending from a side of the housing; and a ballast plate mounted to a housing lower side. The ballast plate is shaped as a planar member having ballast plate sidewalls and includes an adapter plate bottom opening disposed on the ballast plate; and a retainer retaining the ballast plate to the housing. The retainer is secured to the ballast plate, and the ballast plate directs the wire from the side of the housing through the adapter plate bottom opening. An adapter plate front opening is formed on the ballast plate and receives the plurality of lead wire extending from the side of the housing.