Chapter Five: The Flayed - S3-E5
Visible crew/equipment: While Bruce chases after Nancy and Jonathan they hide in the OR, then Nancy picks up the red phone and shouts, and in the following closeup of the ceiling mounted domed light, the upside-down reflection of a crew member wearing shorts and sneakers can be seen quickly. A few minutes later, after Jonathan jabs scissors into Tom's throat, when Jonathan leans back out-of-breath there's another closeup of the surgical light, and we can see the upside-down reflection of the cameraman's arm and part of the camera as it moves closer, then it's visible again a few shots later. (00:43:10 - 00:46:40)
Chapter Four: The Sauna Test - S3-E4
Visible crew/equipment: When Mike and his friends are discussing the Mind Flayer needing a new host, El asks how they'd be able to tell if someone is a host. Then it cuts to Hopper and Joyce pulling up in front of Town Hall, and before Hopper gets out of the car the boom mic is reflected on the squad car's window. (00:14:25)
Answer: They're both muscle cars, but that's about the extent of the similarities. But the 70's were filled with a lot of muscle cars, so some car models may look a bit like another's. Billy's car is a late 70's Chevy Camaro (probably a ‘79). Mad Max's car is a 1973 Ford Falcon XB GT. Incidentally, the Ford Falcon was produced by Ford Australia and wasn't an American car, or even sold in America (as in not sold at dealerships).
Bishop73
According to the experts its a Camaro '78 with added vented side fenders.