Boy can I help here. I broke my clip on the new master and had to do a ton to make it right.
As far as I can tell there are 2 types of clips that hold the rod into the master.
The first looks like a "clover". It is made of spring steel.
The second type looks like a neoprene washer.
Yours is probably the steel "clover".
For removal of the rod to the master - - - - - Hold the master or the "master puck" into a vice and then pull on the rod. It will take a lot of force. You will break the clip.
If it is the neoprene type, they pull easier but round off.
I am thinking you have pulled the "SNAP ring that holds the piston into the back of the master, so you need to put the "piston" into the vice and pull hard on the rod.
Now for the fix - - -
For me I bought a cheap rebuilt master and pulled the clip because I didn't want to leave the clip out. My friend "The Greek" posted about a source for the clip.
Check out this thread that I had used http://www.allfordmustangs.com/forum...follow-up.html
I will also post a picture of the "clover clip as soon as I remember where I posted it. LOL
For me, I would replcae the clip, but the rod will come out for sure, Print Dad
Here is the clip I spoke of: