This is a massive piece, with forty voices (though they almost never sing all at the same time). Nevertheless, the score is about three foot tall so it’s difficult to get your bearings when you see it on the page.
Here’s the score broken down into manageable chunks with two choirs per file. Check the file before you print it as there’s four pages of natter before the music starts, and sometimes another page at the end.
This is the one you need now:
You don’t need any of these at the moment:
…more to follow.