Holy Gamoses what a pain in the ass!
Mrs WD came out of the shower at about 6 AM in a panic because the water wouldn't turn off. I calmly and confidently started trying to take it apart about 7 AM. Got a new cartridge that was supposed to fit as soon as HD opened.
First I tried to take it apart using the stupid tool Moen includes with its new cartridges. I could hear the old cart. laughing when I pulled it out of the package.
I juggled and worried it with pliers, screwdrivers, and assorted implements of destruction for about an hour.
Then (after watching a video) I drove two wood screws into the cart. to have something to pry with. No joy.
Next i drilled the center out and tried an Easy Out. Nope.
Then I tapped it and screwed a bolt in and used a slide hammer on it. The threads pulled out.
Then I screwed a piece of 3/8 iron pipe into it and applied the slide hammer. Again, it pulled out.
By then it was 2 PM and I was tired hungry, pissed off, and desperate, so i took a torch to it and tried to burn it out. After a nice chat with the lady at my alarm company I got them to put the alarm on test for a while so I could burn the crap out of it.
Lots of smoke and fumes later I had it in small enough pieces to dig out with a screwdriver.
Polishing the inside took until 4:00.
I had to take it on faith that the new cartridge was the right one because I could find no model number on the valve and the old cart. was a pile of charred cinders.
It took another hour to fight the new cart into place.
I had several minutes of panic when the stem would not slide in and out to turn the water on. I inspected the cart and noticed there was a rotary position where all the holes were covered. I've experienced valves that do on/off and mixing just by rotating the knob. I called Mrs WD to confirm that this one was push pull on/off. WTf?? I desperation I jammed it back in, just hoping to plug the hole so I could turn the water back on and take my own shower and deal with it later.
To my surprise it worked! It works differently, but it goes on and off and mixes the water!! Mrs WD thinks I'm a genius. I never let her see me sweat.
Here is the valve with the guts burned out of it.
This is what the old cart looked like when I finally got it out.
The old cart. may or may not have looked like this at one time.
All buttoned up and, miracle of miracles, it works!