Ok, so my house is older (no copper). What's the easiest way to hook up an ice maker to the steel pipes? Can I just drill a hole in the supply pipe and use a saddle valve? If so, what size hole do I need to drill? On all the saddle valves I found at home depot they only mention copper pipe. I know a lot of people hate saddle valves, but I really dont' want to pay a plumber to come out and put a "T" in my existing supply line.