Grandmaster plan

[rachmaninoff_forever]

Alright so this is how it is...

I'm singing in an octet right?

And we get to sing stuff

And I was like

YOOOOOO!!!!

What if...

I transcribed the the Ondine from the Gaspard de la Nuit and the rach 2

For voice!!!

That would be so freaking cool!!! 

Alright I'm done.

[awesom_o]

I think it would only work if you had Bobby McFerrin in your octet... and several others like him!

 

Good luck!

[quantum]

I want to hear that!    

Try out some small section just to see how it works for your octet.  Listen, make adjustments, proceed with version 2, repeat.  The other musicians may also have suggestions in how they might vocally render the music.

[pianoman8]

Frankie Valli can sing all the high notes... not sure who else I would get.
Eric Carmen can sing the theme from the second movement:), just like he did in All by Myself

[j_menz]

IMO, both would require highly developed transcription skills to work. Perhaps something more straightforward would be a better starting point, with these saved for when you have had some practice.