I pulled down the fixture, removed the ballast and fluorescent bulb holders. I then installed a small SPDT switch in the housing. Using
Amazon ribbon LEDs, I fit 5 strips in each light base. I wired one side of the switch to turn on 3 strips, the other side to power all 5 strips so I had medium and high settings. When reinstalling the lights in the ceiling, I added a small 12v voltage regulator into the power so the LEDs aren't over-powered when the converter/charger is plugged in. There are many threads about doing this conversion, you might use the search box with the Google logo to search for more information.