how traveler stop fitting disassemble

[davil]

Hi
have these two traveler stops that I like to re use as a base to mount cheeck blocks but the plunge top is on my way,want to remove them,these are spring load and set into the traveler holes stops.
Cannot figure how to remove the plunges,no rings or other visible means of locks that I can see,suppose can always cut/grind them but must be an easier way?
here two pics.

[Tetepare]

First photo shows what looks to me like a capture ring on the inside.

[davil]

thanks
you are right, is a ring and made of soft material,almost like the back of some kind of rivet like plug but continues as part of a tube?,more likely will have to dremel it out,does not have any way to open.