Strips. And also mount some on the sides. For side lighting. I love my samsungs. So much that I'm building another one for my other flower tent. And right now you can get the bridgelux vesta strips on the cheap. 280mm for under 5 bucks. Or 560mm for 10 bucks. The 560mm would fit perfectly bc they are only 22.04", long. I'd just line the top and each side with strips. Run them horizontally. I'd put 10 on each side and some ontop. Mount the pans to the inside of the fridge then mount the strips to the pans. But bc youd be running that many strips. You could run them softer for heat. You have more sources of light. Or if money isnt ab issue for your build. Go with 1120mm samsungs and stand them up vertically on the sides. And 560mm on the top. They would flower the shit out of a fridge. Post some pics of it after you build. Be pretty cool to see finished up.
