Steve Vai gave the following advice about 12 years ago,,,learn 7th chords ,say Amin7th, in at least 5 different posistions on the neck,then learn the notes in the chord,and play them as arpeggios.Continues this with all the 7th chord variations possible.This greatly helped me memorize the neck,good luck.

http://artists.mp3s.com/artists/355/dead_leaves.html