This is a neat print in place adjustable lithophane stand i made for lithophanes made on the 3D Rocks site with 150mm used as the max size. I tested it on 4 different curvatures at this size and all worked great. The slots have 2 different radii in them to allow them to function. They can also be scraped to fit if needed. It is designed to use 5v led strips as the light source and a USB cable for the power. The stem is 120mm tall and the legs swivel in and out to adapt to your lithophane. I printed this with 5 walls and at 40% infill to test it because I know I had to free up the legs from the modeled supports, but I think these both can be reduced if needed.
Swivel legs to free them from modeled in supports. It should not take much pressure.