So it's been a very long time - years even - since I posted this, but we finally removed it! My dad and brother came and helped me get this out. We did NOT put up plastic, which was a HUGE mistake. I ended up with greasy black dust on everything. I had to wash the entire house down with straight Dawn. As, of course, I had every fan on and all the windows open, LOL. Here are some pictures.
At this point, it's been mudded in and dry walled. My brother will sand it and remud it when he has a chance and then we will texture and paint. The floor needs to be built up underneath it too as there is a 3/4 inch drop to subfloor there. All in good time:)
Since it's based on his availability, it will probably be months from now before it's done, but I'm very, very happy to have it gone!
I'm going to try and find a pantry and cabinet to match the existing ones, but in the mean time I simply put the $10 CL ikea unit I had been using as a pantry (in the living room, lol) and slipped it into the slot.