I am trying to install thin LED recessed lights in my hallway. I need to remove the old ceiling box, as shown in the picture. I tried to remove the box for the whole day but was unsuccessful. I cut the drywall around it ad is sure that it is not fixed with a joist or anything.
I removed the punch knockouts and found that the whole ceiling box was connected to three conduits using the connected, as shown in the picture below. The conduit brings in the wire for a three-way switch system to the said ceiling box. There are the big nuts that are tightly screwing these conduit connected at the backside of the box.
Please give any suggestions as to how to remove the box. I still want to use the same wiring so don't want to damage the conduits or wires coming out of them.