I. Soprano sax in Bb:
II. Tenor sax in Bb:
IV. Bass guitar:
V. Vocal part sample:
Big leg Emma, intro and verse (arr. FiftyII50).
Note: the vocal part is included in an mp3 file I also received, upon which I'm basing part of the analysis (like the harmony upon V being a B chord).
Idem in the literal Zappa in New York execution, stressing the mingling of Dorian and Mixolydian in the vocal part too.