After plenty of research on the subject of lighting, I bought these items. Cost was a little over $50
LED Strip Lights
https://www.amazon.com/gp/product/B00WQFP3AO/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Power Supply
https://www.amazon.com/gp/product/B00K71VMCW/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Corner Connectors
https://www.amazon.com/gp/product/B01DM7F052/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Inline On/Off Switch
https://www.amazon.com/gp/product/B01FT4RBBM/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
I've thought of upgrading my lighting in my safe at some point - looks like a good option you've found.