Will a gas tank from a '68 C body fit a '70 C body? I realize they are different generations and the evap connections will likely be different but would the tank itself bolt up?
You'll probably need to re-use the existing filler tube. The replacement tanks fit from '66-'73, with differences in the number of connections for vents, evap emissions, and such. Check the catalogs at www.rockauto.com and the SpectraPremium website for verification.