I'm confused! Did some reserch and bought a 40gb hard drive to put in place of the original 20gb. 40gb does not fit! What are my options here? All my rides are set up for these older Ipods so I just need the extra space and can't upgrade the whole fleet to newer componets. I know some of the click wheels had larger hard drives, but were they also fitted with different back cases to fit the larger drives?