Okay I am installing leopard on my imac using leopard assist. Everything is a go until I get to the part on the leopard install when it told me I didn't have enough room. Well leopard needs 5.9 gb to install if I cut out all the extra stuff and I only have 6gd hdd. (I have a wd external hd but my current os wasnt supported.) So anyway I erased evrything in disk utility and it says I have 5.9 free but I actually have 1gb that is still being taken up thus I cant install leopard still. How can I completely erase the hdd so the entire amount can be used? Thanks.