I know this is an old thread, but when googling its the only thing that came up. I figured it out eventually so posting instructions incase anyone else comes across it. Sorry ahead of time if I'm using the incorrect part terminology.

https://imgur.com/a/bVBxSs4

1) Picture - Like mentioned above you have to hold the spring compressed. The easiest way I found is putting my little tool bits in between the body and the inner slide pin.
2) Picture - Once the spring tension is off you have to separate the pin from housing by sliding them apart. If its lubicated it will probably not separate from jiggling and I needed to use a small pick to get it.
3) Picture - Here you can see it more clearly once the outer body is removed.
4) Picture - Once those are apart the pin will push through the hole
5) Picture - Once the upper section is removed the pin in the lower section will push out the bottom
6) Picture - Just a note here for reassembly that there is a flat spot on the firing pin that seats with the inner slide.

Another note when you start I didn't pay attention to the orientation of the handle and the bolt so make note of that before you start and it will save you some time putting it back together.

Hope this helps someone