Did this right after the new refrigeration was installed. cheap solar powered remote digital thermometer. Yes it's reading 36
Box is nearly done. Don't know if there's a paint that will stick to polyethylene that the old box is made of. Still need to paint the lid finish the weather strip,and decide on the the sealing the foam to the inside of the bottom
Not hopeful even after reading this: "Krylon® Fusion applies easily to a broad range of plastic surfaces including ABS, PVC, polypropylene, polyethylene, fiberglass and rubber. It also can be used with excellent results on wood and metal, so it is ideal for color-coordinating multiple surfaces when one is plastic." Guess I'll try it someday.
Oday's boxes were well insulated. I did add some on the engine side aft and forward sides.