On my 1970 Nova, using 30"x9 Hoosier Radials we used a 5.5" backspacing on a 10" rim. We did, however, need to do some "massaging" on the inner closest points with a sledge hammer. Also, we had to ensure that the rear end was perfectly centered and correct it to get equal spacing from side to side. As previously mentioned, also had to roll up the lip so it does require some attention to avoid rubbing, but will fit. We had also used a shortened full size 12 bolt housing, so your housing could vary slightly as to width. Best to borrow a wheel/tire and test fit if possible before ordering your wheels
Grant