Brake dragging on passenger side,advice/help needed

ok some more looking/replacing today.Replaced the caliper to have it do the same thing,not surprising but was hoping,lol. What I did find though is the passenger side caliper will rock when applying the brake and if I can move it back it frees up so I'm thinking my adapter/mount is worn out. The drivers side does not do this. So does that sound like the mount being worn or should I be looking elsewhere???