Watch the Flat 6th: Alt. Dom. Over II-V-I online guitar lesson by Kenny Wessel from Shades of Jazz
In this video segment, I'll demonstrate how to use the major b6 pentatonic as an altered scale in an II-V-I progression. The progression that we're playing over is one bar of D-7 / one bar of G7#9b13 / two bars of Cmaj7. We'll play a D minor pentatonic over the D-7 chord, we'll use the Eb major b6 pentatonic over the G7#9b13, and use a C major scale over the Cmaj7 chord. (You can also play a C major pentatonic- A minor pentatonic, in addition to many other choices.)
This might sound a bit ‘heady' using all these pentatonics in different settings, but once you get the hang of it, you'll be flying.