In today's industrial practice, requirements specifications are essential as an agreement between two or more stakeholders on what has to be developed and delivered. To store and communicate these requirements, nowadays, requirements model and Functional Specification Documents (FSDs) are commonly used in interdisciplinary environments. Although these information sources capture identical information, the technical coupling between them is inadequately managed. This is specifically realized when changes are applied to these documents, as such changes are typically too difficult for interpretation by machines. To address the problem of potentially occurring inconsistencies among heterogeneous information sources, this paper focuses on the coupling of changed documents to their origin models. We propose a general Model-Document Coupling by applying a systematic Text-to-Model (T2M) approach during the reverse engineering of changed FSDs. We evaluate our approach by a developed software prototype at the example of a modified FSD and corresponding requirement model, that describes a lab-scale industrial demonstrator. We discuss the capabilities and limitations of Model-Document Coupling regarding the transferability to industrial practice of Cyber Physical Production Systems (CPPS) environments.