I got a copy of Macintosh Family Hardware Reference yesterday. It looks like a great book, but now I'm more confused than ever about how it differs from Guide to the Macintosh Family Hardware. I had thought that GttMFH added coverage of the SE and Macintosh II that MFHR lacked, but MFHR covers those. So maybe GttMFH is basically the same book, just with some minor corrections and updates?