Two Mark 3 models appeared in scrapyard scenes in The Sweeney - both gold 1965 cars.
This photo is from the first of the two feature film spin-offs and shows a couple of crims meeting an unfortunate demise (including Brian Glover who seems to have given up his previous career of bullying schoolboys during PE lessons).
On the left CPH229C can be seen supporting a white Mark 4 Zodiac. According to IMDb filming took place in April and May 1976 which means it was only about 11 years old:
View attachment 162339
An even shorter life was experienced by FYR535C seen here in the episode entitled Big Spender which was apparently filmed in June 1974 thus making the car only around 9 years old and so quite a bit younger than those around it:
View attachment 162340
Rust was always a problem with cars of that period and with their 3 litre engines the values of these Zodiacs would have plummeted after the 1973 OPEC Fuel Crisis meaning that, despite being Ford's top-of-the-range offering, many met a pretty early end which in turn has lead to such a small number of survivors.