The work demonstrates the benefits of using digital methods for the development and optimization of large assembly manufacturing networks. Although an aircraft assembly has been used for this work, the methods and advantages of digital manufacturing techniques, which are demonstrated here, are equally applicable to any large assembly process, such as those used in the automotive, railway, and shipbuilding industries. The introduction of manufacturability into the design arena using advanced computer aided methods means that manufacturing engineers can operate more directly in assembly planning and concurrent engineering design. Network analyses carried out on the final assembly operations for a regional jet fuselage section using a methodical, step by step approach, shows that the process efficiency for workers carrying out fitting operations can be more than doubled when compared to existing shop floor performance figures. The more efficient use of operator time results in a simulated 19% improvement in financial efficiency, as the actual working hours required for assembly are reduced to below budgeted levels. The simulation predicts that these results can be achieved with one final assembly station. With two stations currently in use for the fuselage section, this means that a significant financial saving is possible in tooling expenditure.