All the films are black and whites, so I'm not expecting colour shifts
That's what I get for not reading the post fully!
It's been some 20 years since I was inside a darkroom, but I remember a book from Kodak called the Black and White Darkroom Dataguide, or something like that. IIRC it was only about Kodak products so it might only be peripherally useful with Ilford. Of course, you could also go to:
http://www.ilford.com and ask them...
Mike.