Mac, It is helpful and perhaps I did not explain myself correctly as to what I meant with my roman numeral cheat sheet.

First chord of 500 miles is E-7, with the melody using D B B A F# and D, I think Dorian for E is the right scale choice. When I write out E Dorian notes, what I see there is the notes for D Major.

So, D is the 7th degree of the E scale, hence I wrote VII Major scale, not for the key signature for the song( which appears to be C), but for the specific chord.

Same song, next chord is G-7, which looking at the melody notes also seems to call for G Dorian, which when I write out the notes for it, I see F major. F is the 7th degree of the G scale so I wrote out VII Major again.

Next chord is Bbmaj7 and with the melody notes in the transcription, looks like it calls for B Lydian, which when I write out the notes - lo and behold we have the F major scale, so I wrote V major, since F is the 5th degree of the Bb scale.

B-7b5 with melody looks like B Locrian, which happens to be C major scale.

Am7 with melody looks like A Aeolian, which turns out to be C major.

And so on.

Since posting this here, I have had some good replies over at the Jazz Improv class forums and some were concerned that I would concentrate on the major chord notes of those cheat scales, but I can 'see' the proper chord notes in these major scales (for example, with the B-7b5, with C major over top, I know that B,D and F and A should be emphasized, but I also know that I have the luxury of simply using C major scale notes for approach and decoration notes in between)

So in short, my cheat table above relates to the degree of scale for the chord in question, not the key signature of the song.

I've tried this at the piano this Saturday morning, playing the proper chords left hand, and using my cheat major scale look-up, and to my ear, my noodlings actually sound pretty jazzy. There are a couple Altered scale choice chords that I'm going to have to work on. I'll post a link here probably before the weekend is out.

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