This study aims to develop a methodology for evaluating the crashworthiness of cabins in converted dual-cabin vehicles based on mass-produced basic vehicle frames. While traditional assessments have relied primarily on physical crash testing, advancements in computer-aided engineering (CAE) have enabled more efficient virtual simulations, significantly reducing the need for physical prototypes-especially in the case of low-volume, modified vehicles. The research employs LS-DYNA and ANSYS Static Structural to simulate frontal crash scenarios and assess driver survival space. Three key aspects are investigated: (1) the impact of varying plate thicknesses in less load-bearing regions, (2) the structural behavior of different A-pillar designs, and (3) the improvement of survival space in accordance with ECE R29 Test B conditions. The simulation results give structural regions with low load suitable for thickness reduction and the appropriate thicknesses size for this regions is 1.75 mm. With the different obtained reinforcement solutions result, it was possible to decide longitudinal reinforcement is the best method, resulting in about 5% reduction in penetration compared to the original model.