Best thing to do with those saddle valves is to send them to the landfill. They are noted for their failure rate. They seem so simple and easy to use that the average homeowner thinks they're really great only to have grief later. The best thing to do is to cut the supply line, put in a tee and a ball valve. From the valve you need to get the necessary fittings to reduce the pipe size down to the icemaker supply line. Probably can do the job for under $15 for material.