I had recently changed my brakes on my 79 ranchero and i had lost the dust caps on a test drive somewhere. I picked up a set of replacement dust caps at the auto part store. They put my car in the computer and gave me the right part # to fit my car. When I got home to put them on, they would not go on all the way. It seemed like they were too small. I double checked and i had the correct part. Is there some kind of a trick to putting these dust caps on?