To meet the demand for multi-variant and small-batch production in the automotive manufacturing industry, this study addresses the challenges of low line change efficiency and poor equipment universality caused by dimensional differences in headlights across multiple vehicle models. A flexible fixture system based on D-H modeling and vacuum adsorption technology was developed. By reconstructing 3D surfaces to establish high-precision models, the system achieves force adaptive adjustment and rapid model switching. The modular design increases universality by 70%, enabling quick adaptation to various headlight assemblies. Practical applications demonstrate that the system significantly reduces changeover time and production costs, enhancing the flexibility and intelligence of assembly lines, thereby providing an effective solution for mixed-model production.