new privacy settings help!!

Ok so, this privacy settings are driving me nuts!! i have succesfully turn my wall private to the public but, I have people in my facebook who I didnt allow to se my wall. This I did because I htought it will be rude to deny the friend request so, I accepted the friend request and then in the privacy settings I will put their names in the except this people box and save the settings and VOILA! they couldnt see my wall. Well now I cant do that I tried everything I went to the priivacy settings and I check that box that said custom and put the name of the person in the except this people and went and preview the profile and they can see everything like I never did any changes. then went and did the same with tagged and post by other people and it worked, but they can still seee my old post made by me! That happens if I add someone new too, I can hide my wall from them I either have to turn down the friend request and go manually and customize everypost I ever made!!! This is not fear it has to be a way!!!! Any help is deeply aprecciated thanx!