Model-Based Systems Engineering (MBSE) has emerged as a de facto standard practice for complex systems development. However, despite standard frameworks, methods, and tools, the MBSE practices in industrial contexts are far from mature. This is particularly true for traditionally hardware-intensive industrial systems and complex products such as heavy construction machinery. This paper outlines a light-weight MBSE methodology developed within the construction equipment domain. The approach is based on customizing a general MBSE methodology, such as RFLP, guided by a core ontology for architecture modeling. The ontology defines the main architecture concepts and corresponding modeling views to develop an architecture baseline for the corresponding system model. The initial architecture baseline is developed bottom-up instead of a traditional top-down approach. As we demonstrate in this paper, the minimalist approach paves the way for faster deployment of MBSE in industrial contexts with low modeling experience and legacy development silos across electronics, software, and hardware domains.