In the pictures where that feature appears black, it looks like sections of fuel hose on some sort of straight rack. Yet, in the close-up shot it "appears" that the rack, if that's what it is, has a curve to it. Its definitely a puzzlement.
All of the railings, radar and additional details are done and I've applied a coat of Mr. Surfacer 1200 with my new GREX airbrush (first experiment with this new brush).