I purchase a Ford Fiesta rear light cluster and found the top plastic post was too long, leaving the cluster about 5mm proud of the chassis when put in situ. I only resolved this by unscrewing the metal threaded bolt from the plastic post and reducing the size of the post it by cutting it. I then had the problem that the metal threaded bolt was too long to screw into the plastic post so I had to re-use one of the three threaded bolts from the part I was replacing. This is such a basic flaw that I really can't understand how it would get through a basic quality check.