Model-Based Systems Engineering (MBSE) methods have developed a strong foothold in the design space in industry. These methods have proven fruitful when the right method is applied to the right problem. Reliability, Availability, and Maintainability (RAM) is an equally important area. Currently, there is a gap in applying a methodology to integrate the two in the design process, particularly when the design is complex. This work attempts to provide a methodology that results in the successful integration of RAM and MBSE that can be used during the early phases of design. The methodology was developed after an extensive literature review, followed by the illustration of the methodology through an example of a steam turbine fuel system. Each step of the method is applied and explained in the illustrative example, to include figures, tables, and calculations demonstrating the effectiveness of the method, concluding with evidence for validation.