Presumably the 260s were parking behind the cameraman, at the point where David drives past you can hear a metallic scraping sound probably from the car parking behind out of shot. This is caused by a thick corrosion build up between the clutch bell housing and the thin engine back plate behind the sump area, this distorts the back plate and bends it towards the rear of the flywheel to the point of skimming it. When the clutch is depressed the natural end float in the crankshaft allows the flywheel to rub on the engine back plate causing the scraping noise. This can be remedied by removing the two lower back plate bolts and scraping off the corrosion from the clutch bell housing and gently shaping the back plate for clearance before refitting the bolts...