This derailleur was incredibly stuck before I took it apart and the only joint that’s giving me trouble is on the underside of the parallelogram.

Has anyone here ever taken one apart? I’d like to know if the grey metal piece that actuates the guide can be removed from the main plate. There’s a similar grey metal piece inside of the parallelogram that could be removed but I’m trying to figure out how to pull this piece off.

I’ve tried WD40 and PB blaster. Curious to hear if anyone else has taken one of these apart and has a tip for me.