Yeah, you add a sharp between the 5th and 6th scale degrees, making for 8 notes in total. Then if your harmonize that scale by playing every other note, you end up with alternating inversions of the root maj6 and the diminished chord.
This is the theory behind drop 2 voicings is it not? Being that as you alternate b/w Maj & dim voicings you copy the top note of the RH in the LH, I like to add a chromatic flourish to the LH note and it gives you a very George Shearing sound.
But wait there's more! Not only does this function harmonically, it also functions melodically. The added scale tone makes it so that a chord tone ends up on every down beat when playing in eighth notes. I've actually found that it doesn't matter where you add that extra scale note, you can do it all the way up and down the piano anywhere you like as long as you get chord tones where you want them.