Thought someone here might find this helpful:
As many of you understand our Mustangs traveled down the assembly line on a series of mounting points (8 in total) that attached the car to a moving dolly.
At 4 of these points the car was bolted to the dolly and at the other 4 points the car simply sat on stands. Many of you have found your own way to reproduce the look and feel of these bare metal spots, here is what I'm trying with the most recent car I'm helping with.
Original examples of Dolly marks