The ever increasing need for improved automobile fuel economy led to the eventual use of light weight materials such as aluminum amoung other things. This paper discusses techniques and problems of assembling aluminum and steel sheet metal stampings into Hood Assemblies. This paper does not attempt laboratory type research in fastening methods, such as spot welding, but discusses the application of these techniques from a Fabrication Plant point of view. In particular, this paper will discuss two hoods and their respective assembly processes. First, a low volume (30,000 units/yr.) bimetalic hood used on a 1975-76 “E” body, and second, a high volume all aluminum/all steel hood for a standard sized car.