I agree Wolf’s books are good to have along. It’s been several years since I used them, but I recall a few places in NM where I had some minor problems because they were written for SOBO. I also recall at least one area (MT?) where there were both NOBO and SOBO texts.
I felt that Wolf’s maps are generally not required if you have Jonothan’s maps and the DeLorme pages. One exception I can remember is the Florida and Mimbres Mts in So NM which were not covered by the Ley maps at that time.
I also made it just fine without a GPS. Constant attention to navigation is needed, which is a good idea whether you have a GPS or not.
Garlic