the 70 novas back!

ok my newest question, on the drivers side rear wheel, even after i put the shackle lift on it rubs the outer rim of the wheel well!! it gets really bad when i turn left corners. and on the other side, the wheel is at least 4 inches in from the edge of the wheel well! so its not that big of an issue its just wearing a small channel in the outer wall of my wheel which could be dangerous if i race it. i mean goin fast is cool, but its also equally as important to be able to stop and also not die in a ball of flames.(well that actually would be pretty hardcore!) so i was wondering do i need to lift the differential and undio the ubolts and slide the sucker over an inch or so or what? im not sure why this would happen and it started happening about 3 weeks ago, its not to pressing so ive waited on it but im wondering if it will badly mess up my driveshaft or something, ya know anyways you guys are awesome and i totally appreciate all the wisdom your givin up for free!!! see ya soon

ok so first where would i find the centerbolt that streets was talkin about
second where is the C clip that csf was talkin about and actually tyhis was happening before i had the shackles on so the chackles just make the scraping less frequent, because the whole wheel isnt inside the wheel well, only a small edge. so should i jack the diff up and check the leaf springsand stuff?