Hi Falquian,
I am facing a similar challenge, though at this point just with Windows. Joel's article you linked helps, but it seems there are a huge number of changes in this upgrade vs. what we have been used to. I was really disappointed that the history of installing views against most of the "legacy" tables seems to have been dropped in 7.0 and 7.1 (though it was in the product from 5.0 to 5.5, and 5.5 to 6.0). I'm wondering if it might not be easier (though somewhat more slowly-performing) to create views on the 7.1 tables that match our old well-known tables and views we're used to from 6.x. It would (in theory) really speed up migrating reports over too!
A few notes (though I suspect by now you've figured this out)...
The Serial Number is captured as part of Basic INvenotry in Inv_AeX_AC_Identitification.[Hardware Serial Number], alond with Inv_HW_Computer_System in [Identifying Number]. Most of the *_Unix_* tables have been flattened and merged into common tables/views. Good luck!