GMF geometrical structure for the best-fit presented in the core of the paper (top row) and for the one obtained from the second local minimum (bottom row). We show the best-fit ASS GMF models in the (x, y, z = 0) and (x, y = 0, z) planes of the Galaxy for the three best-fit n_d models obtained from the adjustment of the I₃₅₃ map. From left to right: n_d ≡ ED, ARM4, and ARM4⊕ED, respectively.