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I'm planning to add a set of recessed lights to an existing circuit in my home. The existing circuit is fairly simple: one light, controlled by one switch, and there is no insulation in the wall or ceiling.
My dilemma is in adding the fixtures into the circuit between the existing fixture and the switch. I will need to splice additional wire into the circuit, but I'm certain there isn't enough slack to draw the existing line into the fixture's junction box to make the connections.
Should I run new line from the existing fixture to ensure that the connections happen inside the box? Otherwise, can I splice a short segment into the existing line to get the slack I need?