[Vwdiesel] Windshield Washer pump

[Doug & Pam]

I found a replacement pump at the local auto parts store. It is almost an
exact match. However, I haven't removed the old pump from the tank. The old
pump is secured to the tank on the inside by a push-on locking washer that
has the metal tabs all around the inside circumference that will bite into
the nozzle to prevent removal.

Is there a way to remove this locking washer without destroying it or
damaging the tank? The only access is from the fill hole and the washer is
positioned edge-wise to the hole and directly below it because the pump is
mounted horizontally. I don't mind destroying the washer to get it off but I
don't want to damage the tank.