Retrofit lighting kits allow for the reuse of fluorescent lighting fixture housings, already in place, while retrofitting new assemblies that increase efficiency, reduce energy consumption and demand, and reduce ongoing maintenance costs. The advantage of one retrofit kit is to quickly replace inefficient T-12 and T-8 ceiling mount 2 bulb fixtures, with a higher quality, and more efficient lighting source, while concurrently lowering the cost of operation, and maintenance. The advantage of another retrofit kit allows the installation of compact fluorescent lamps, of several sizes and configurations, to quickly replace the inefficient T8 and T12 lamps and service equipment, used in troffer style fixtures. Deployment of these kits, reduces electrical usage, eases servicing of the fixture, and reduces heat buildup in the fixture.