12 volt motion detectorIf you want just white light you can buy rolls of white led strips on Ebay. Then use the motion detector shown so you don't have to fumble with switches. Parallel the power going to the existing light in the bay and you can still turn the old one on if needed.
If your bay has uneven surfaces where you want the light buy some thin wood strips and stick the lights to that and then mount them.
I use the strip lights in several places. One of the motion detectors is used in my hallway to make night time trips easier.
Another detector is used in our closet.
Additional strips have been added under the cabinets over our kitchen area. Much better lighting. Running some in the cabinets make finding things easier too.