Large-scale civil engineering construction machines, like a Diaphragm Wall Hydraulic Grab, need to be operated safely and efficiently. Implementing assistance systems can significantly enhance the efficiency of handling these hard-to-control machines. This paper evaluates several developed assistance systems that support untrained operators handling civil engineering machinery based on their level of automation. As experienced operators can efficiently handle large-scale civil engineering construction machines based on expert knowledge, their mental model was collected during the operation and used as input to design assistance systems. The paper discusses the use of the developed assistance systems based on results from a focus group of experts, in which the feasibility of automation levels is discussed. A survey was conducted before the development phase to obtain an unbiased perspective on the development of the systems. This survey aimed to capture the current state of the automation levels and the desired state with the inclusion of assistance systems. Following the successful completion of the project and the development of technically feasible solutions, the expert group was surveyed again. This subsequent survey focused on reevaluating the steps of their functionality. A detailed description of why the developed solutions are only sometimes beneficial from an operator's point of view is given.