Little help with panhard bushings please

[Zonaman]

I'm going to replace my worn out panhard bushings with the polyurethane type. The kit says I'm supposed to reuse the orginal metal outer sleeves. Are those sleeves supposed to pop out with the rest of the bushing or are they likely to be frozen in there? Is it necessary to remove them from the rod ends to fit the new bushings? Any other tips appreciated

Thanks.