Chances are if your inner and outer rocker panels are rusted, these tie in panels are rotted out aswell. These are what the inner and outer rockers attached to. Prospect-D tie in rocker panels are a direct replacement and help save you the ease of doing a questionable patch job. Prospect-D is the only producer of these tie in rocker panels.
These will fit 240Z and early 1974 year 260Z. These will not fit 2+2 models. Prospect-D as of yet has not confirmed fitment for the 280Z (buy at your own risk).
These panels are constructed from 20G CRS which is the same thickness as the factory tie in rocker panels. Prospect-D hand shapes these panels with use of professional tools. A light coat of weldable rust preventative primer is sprayed at the end to protect until installation time as an option. After all these are made to replace rusted panels, not recreate rusted panels.