When Chin is following Cunningham, he is shown driving a 1970 Ford Custom 500, but on the inside shots of him, he is driving a 1968 Ford Torino.
McGarrett picks up Cunningham's rifle and misidentifies it as a Dutch made AR-10. Merrill, the gun expert, corrects him by misidentifying it as a prototype to the M15. The gun is neither - it is easily recognizable as being from the AR-15 series of rifles firing the 5.56mm round, either a fully auto M16 or semi-auto AR-15. In the wild guess department, McGarrett was a little closer to the mark where the AR-10 is actually designer Eugene Stoner's precursor to the AR-15, but is larger and heavier as it fires the NATO 7.62mm round. The M15 was a member of the M14 family of traditional wooden stock battle rifles and cannot be confused with the lightweight plastic and aluminum AR-15/M16 even in the dark.