I am working on a homemade keezer project. I received a free medium sized fridge and have since bent back the freezer tray and rewired the thermometer. The next two steps involve modifying the walls, but I am nervous about hitting a coolant line. I am looking to drill a hole in the top for the tower and to shave down the sides to fit two 1/6ish size kegs. I am almost certain the whole thing is cooled by a freezer tray. I look at the tubing coming out of the compressor and have felt around it when it is running full speed. I was wondering if there was any way to test this for sure. I uploaded a photo of the front. I can upload the back when I get home. Any opinions or help is appreciated. (Minus telling me to go out and buy a different/bigger fridge) Thanks all.