I'm going to go and look at a 67 couple that looks like it has some good parts for my fastback. The owner said it has a 9" in it and I told him that car came with an 8". I don't really want to crawl under the car if I don't have too. Just by getting on the ole knees, is there an easy way to spot a 9" over an 8" or vise versa?? Thanks guys!