[Tigers] removing master cylinder reservoir

[Mike Michels]

I'm replacing a GIrling master cylinder with the plastic fluid reservoir.
Need to remove the reservoir from old cylinder and install on the new. How
to remove it? There is a plastic "hat" at the bottom center of the reservoir
which I presume covers a nut or C clip that retains the reservoir. It
doesn't come out with finger pressure, and doesn't unscrew. I don't want to
force it with pliers for fear of breaking it. Anybody run into this?