Functional Safety engineering aligned to an international standard is already a long-lasting discussion. Nevertheless, the requirements of process conformance to assure functional safety have been detailed in description and interpretation. The ISO 26262 is seen as state-of-the-art Functional Safety engineering basement in Europe, the closer interpretation of the IEC 61508 is claimed by assessors in America and Asia. This work shows how stagnation in engineering process improvement is solved by re-engineering projects. The benefits of re-engineering are described in this context. A four month, proven-in-practice project plan is explained. The expected results of such a project are given as generic goals for similar projects. A practice report shows the realistic outcome of such a project for the Chinese automotive industry. The report shows how the motivation of the involved engineers was gained and how existing engineering documentation was used in an efficient way. Examples for typical technical gaps in automotive software and hardware design are explained. A fast way to identify detailed gaps in the test coverage on software, hardware and system level is shown. The measures, which were conducted to raise the safety relevant test coverage to 100% are explained. Finally, the best setup, as well as the high benefits and few disadvantages of re-engineering projects for process improvement, are discussed.