Hi all, I have a...cough cough 1966 Valiant, I know it's a later year but help a girl out. Anyway, I replaced the drive shaft U joints and the straps on the differential end don't have the little "shoulders" that hold the caps in place? I've never seen that before? What's to prevent the caps from working themselves off and me from catastrophe? Perhaps they're just worn away after 50 yrs? I was driving this with no issues previously. Any thoughts would be great! Thanks in advance!