1972 Blazer rear end yoke grease cover

[tabs2471]

Hi everyone.....I have a question about the rear pinion yoke on my 72 Blazer......the dust cover on the yoke separated from the yoke....making a terrible rattling sound because it moves and spins freely....I think I know the answer but I want to be sure....do I have to replace the whole yoke with new cover since they are supposed to be attached? Also, if I do replace it, how much do I torque the bolt back down once removed? I tried looking up that info and seems that I cannot find a direct answer. Thanks!