The 3D reconstruction of the NuScale SMR 17 × 17 fuel assembly, based on technical documentation, began with the HMP and HTP spacer grids. Their structure raised questions about fuel rod support, coolant flow paths and the connections that bring individual components together into a complete assembly. A comparison with a Westinghouse 17 × 17 reference assembly then showed which features they share and which need to be understood in the context of a specific reactor design.