This passage is on page 33 of my edition, in Chapter 2 (Puffin Books, 1995):
" 'There was a whole bunch of them,' Johnny went on, swallowing, ignoring Soda's command. 'A blue Mustang full...I got so scared" ... He had been hunting our football to practice a few kicks when a blue Mustang had pulled up beside the lot. There were four Socs in it."
The car driven by the Socs [that includes Bob, Randy, and the others] is a blue Mustang.
it was a blue Mustang
It was a red convertible mustang.