I disassembled the Intermountain caboose by removing two pins from the bottom of each end railing and separating the body from the chassis (top right). I then drilled a hole in the top right end of the end wall and inserted the LED wire... but it never came into the car body! Which led to the discovery that there was a roof assembly cleverly attached to the top of the car body with eight pins. Once that assembly was removed, I found my wire and marked the parts with a "B" to ensure reassembly would match disassembly. I had to then drill a hole through the top of the car body to allow the LED wire to pass through. As with my Conrail caboose project, research revealed that the NYC also used marker lights at the right rear side suspended under the roof by semi-circular mounting plates. This was replicated by gluing the LED into a small piece of styrene and then sanding the styrene into shape. To route the wires, I cut notches into the top of the end wall on the car body and in the underside of the roof mounting rib (center right).