A frame for a harvesting header has a top beam extending across substantially a full width of the harvesting header and has ends arranged adjacent respective ends of the harvesting header and a midpoint in a center area of the harvesting header. The header frame has a bottom beam substantially parallel to the top beam extending less than the full width of the harvesting header and having a midpoint in the center area of the harvesting header. Vertical main structures connect the top and bottom beams. Diagonal truss members connect the ends of the top beam and interfaces of the bottom beam and vertical main structures. The vertical main structures form a feederhouse interface at the center area of the harvesting header. The top beam and bottom beam are continuous through the center area of the harvesting header. Header drive assemblies are mounted at the ends of the bottom beam.
