Light weighting of cars has the definite advantage of reducing fuel consumption and tail pipe emissions. In this respect, substitution of heavier steel components with magnesium ones can save on weight of the replaced component due to its weight advantage resulting in lowering green house gases (GHG). There are additional benefits when magnesium is applied to complex structures and assemblies such as an Instrument Panel (IP). The possibility of casting single piece magnesium cross-car beams of IP can reduce the number of components to be assembled as wells as ease the disassembly and recovery at the end of life. This study, considering these advantages of using magnesium for IPs, examines and compares the environmental life cycle impact of magnesium and traditional steel and plastic IPs. However, the results indicate that magnesium IPs can have higher GHG impact than equivalent IPs made from others. The technological avenues for reducing the impact of magnesium IPs are examined in an extended study, including impact of primary metal (assumed from China), improvements in casting manufacture and use of secondary metal. These improvements show substantial reduction of GHG in the manufacture of magnesium IPs and improvement in comparative GHG performance with other materials.