These are the two small strut channels attaching the node to the long strut channel.

Using a 1/2" adjustable or socket wrench, remove the four 1/2" hex head screws attaching the old node to the small strut channels.

Be sure to remove the nuts and washers on the inside of the small strut channels as well. (Total: Four 1/2" hex head screws, four 1/2" nuts, and four washers)