Complex sentence: Abandoned Nazi projects or actual vehicles from the period were used as inspiration--the Red Skull's car, for instance, was based on two Mercedes-Benz vehicles from the 1930s, the 540K and the G4.
Split into simpler sentences: Abandoned Nazi projects or actual vehicles from the period were used as inspiration. The Red Skull's car, for instance, was based on two Mercedes-Benz vehicles from the 1930s, the 540K and the G4.