I read the different threads on here about stripping the front master cylinder, my bike is a CB750 K6 but this will help most if not all.
I bent a piece of old round bar to about 80 degrees and when you push the piston down place this in where the lever goes and put the bolt bak in and it will hold the piston down allowing you more room to see and grasp that pesky cir clip
the close up of the thing in place
i ran v hot water over for several mins (in her in doors sink ;-))
the cir clip came out much easier than i thought.
and i used std straight cir clip pliers.
Billy