I thought I had a thread already re some of the attic work I've been attempting. no bx coming out of the sub-panel on the 2nd floor. lots of bx in the attic. I'm attempting to work backwards from some vintage boxes&bx to romex. That's going ok. I got thrown by a switched fixture where the fixture is in the middle of the continuing circuit ('why is the fixture black by itself?'). That bx run is 3-wire (essentially 2 blacks and a white) 1 black for continuing and 1 black back to the switch. First question: Is there a replacement version of that in romex? (3-wire romex?). I'm thinking, if not, just run two romex and abandon one of the whites. Right or wrong? ok so that's two questions. other sitch is half-assed. While tracing the circuit run through the cellulose I got back to another fixture which I need to replace. the old fixture was wired into my traced bx which then continued through with a further section of bx. But, also in that box was a another bx and is the end of some other circuit. I want to -not- pull the bx out but just hang a a traditional 100w fixture with its own pull string (hallway light) on it. The cloth on the wire ends is not good. I've found absolutely decrepit cloth insulation and quite good cloth. The decrepit stuff is usually in a box -- and especially in a fixture (incandescent heat destroys?). I'm thinking I'd cut the bx back a foot or two and find better insulation. then junction that with a short run of romex to the fixture. Second Question: you folks have any pointers on wiring the bx to romex while attempting to preserve whatever ground may be in that bx line? Thanks! Almost Funny back story: I was shocked to find that stray bx line was live. I then spent a good hour or two trying to figure out what circuit it -is- on. Never did figure it out. The only way I can turn that circuit off is to kill the house main at the main panel in the basement -- No sub-panel breaker controls it. Its a peculiarity of This Old House. There are two sub-panels below the attic for what used to be two separate apts. When those subs went in someone forgot to bring that circuit in too. Stranger still -- there's only one bx coming out of the main -- and that's to the boiler. I'm not running 3 flights of stairs for each of about 25 circuits to try and figure that one out. At least not today.