In the new era of digitalization and, there is an ever-rising need for design and production processes capable of increasing systems quality, reducing risks and the chance of errors, while, at the same time, reducing overall production costs.  Nowadays, more and more systems design scenarios comprise a high number of domains, also displaying a remarkable diversity in their nature. However, the tool landscape underlying this conceptual space is, unfortunately, still dominated by closed ecosystems, resulting in the design data remaining in separated silos. In order to effectively deal with such novel, massively diverse, yet interdependent engineering scenarios, we have to propose innovative, multi-faceted tools, even toolchains for supporting every phase of a modern systems engineering lifecycle, while freeing the diverse, multi-domain engineering data from their silos and turning the separate perspectives into a single, interrelated, globally analyzable digital thread. In the talk, we demonstrate a possible approach for that purpose, in the context of an involved multi-domain engineering scenario of a complex electrical harness design process. The toolchain used for achieving this illustrates what can be accomplished with open tools and ecosystems, where system architecture plans originate in GENESYS, E3.series is used for detailed wiring design, while the IncQuery Suite as an integration platform watches over all the phases and provides continuous model analysis, in particular, inter-domain validation and consistency analysis.