Older house in Cincinnati, OH, built around 1920 with all visible knob and tube replaced but some still exists I am finding.
I've got a 3-gang light switch box in my living room which currently has three dimmers which control ceiling lights in the room. One of the dimmers has gone bad and I want to replace all three with z-wave dimmers. The problem is that the old box is not big enough for the new dimmers to fit. I believe the depth is OK but it is definitely not tall enough for the z-wave dimmer to slide in. So, I got an "old work" 3-gang junction box that is larger to replace the old one.
1.) My problem is that I have never seen this kind of box before (the old one) and I'm not sure how to get it out of the wall without destroying all of the plaster around it. I have read things and watched videos about finding where the old box is nailed in and prying the nails out, but this seems to be mounted in some other way??
2.) Also, to throw another wrench into things, there is a knob and tube wire that is in the box and capped (see orange cap on the right of the image attached). This wire is live and on a different (!) circuit than the dimmers/lighting. I found where that wire goes, through the wall into the basement, into another junction box. Funny thing is, there is no matching neutral pair for it! Since I don't know what splices or other things might happen inside the wall that I can't see, I am afraid to mess with this.
I would appreciate any ideas or help!