by I Pik U » 27 Jun 2008 14:36
Sounds like it's an older master cylinder that has a crimped spot holding the plug in.
In this case you have to turn the plug so the flat spot running down the plug lines up with the crimp, the slide it out.
Another possability is you have the springs jambed in the pin chambers, as you've removed the top and bottom pins but not the plug.
Either you will need to lift the springs up out of the plug into the bible, or force the plug out damaging the springs and maybe even scratching the surfaces of the plug and cylinder.

Been playing with locks since '68.