The application of high-precision spherical coordinate scanning measurement systems can significantly improve the efficiency of contour measurement for components with complex curved features, such as aircraft wings and fuselages, rocket cabins, and wind turbine blades. However, the metrology of such systems and the evaluation of contour parameters based on their scanned point clouds pose a major challenge in the industry. To address the traceability issues associated with high-precision spherical coordinate scanning measurement systems, this paper proposes a calibration scheme and related requirements based on large-scale physical surfaces. Theoretical and experimental studies were conducted on the structural design, structural mechanics simulation, and panel alignment of the standard device, along with system calibration verification experiments. The experimental results demonstrate that this method can control the assembly error tolerance within 0.05 mm and reduce the RMS error to less than 0.01 mm, effectively supporting the establishment of traceability for the measurement system's accuracy.