The screenshot below is from the original Crimewatch reconstruction helpfully uploaded by Rookie D further up thread.I think this "kipper" explanation makes far more sense than the Kipper Tie one. Sounds plausible, even if Taggart is telling porkies.
You will see what looks like a Red Sierra parked across from the Fiesta.
The Police weren't aware until later that JC had access to a Red Sierra so it is a pretty strange co-incidence to have one in the reconstruction.
Or is it?