HI Fellow's. I had a serious problem with the c-clip in my master cylinder. The bike had been in storage for about 25 years and the clip was rusty. When I put the c-clip pliers on it the ends they both broke off the clip ( Screwed Big Time Bro. ). After crying, screaming, throwing things I decided to get a Dremel tool with a tiny diamond bit and used it to cut the c-clip. Yes I went through the clip and into the piston. But the piston had to be replaced anyway.
I realize this may not help anyone form previous post. But it may save someone heart burn in the future. Good Luck