Need some help removing rear element from ef 28mm 1.8

I am hoping someone can help me. I have a Canon ef 28mm 1.8 lens. It looks like there is a good amount of fungus only on the inside of the rear element. I contacted my camera shop and they said it's not worth it to fix because fungus always comes back. Instead of tossing the lens, I am going to try to fix it. Can someone please tell me how the rear element comes out? Is it threaded and does it unscrew or are there screws holding it in like some zoom lenses. All the youtube videos I see only show how to take apart the housing. Any help would be appreciated.

There is a video at https://www.youtube.co​m/watch?v=z5apxilBHd4 but unfortunately it doesn’t address the disassembly of what looks like a cartridge that holds the rear element. You’ll see the guy remove the cartridge and move it to the top left of the video. If you get to the point where the cartridge is removed perhaps you can determine where to go from there.

That video is where i got the screen shot from . Looking to see how it would come apart? Not sure if I can just unscrew it or not or if its just one piece.

I don't have one but looking at the cross-section from the parts catalog, difficult to say but I think the rear element might be held in a ring that screws into the housing, either that or just "glued" in place.
There's a little "bit" shown sticking out where the lens joins the housing.