Hi,
The color separation guide and gray scale is either a Q13 or a Q14 (i.e., short or long). I like 64T. I suppose it is one of those personal preference things but it has been my experience that consistency (what if they want more?) and lighting quality are both improved by shooting flat art w/ lights. I would suggest one shoot a test for color balance before committing the whole project to film. A good E6 lab will run one sheet (gray card) for you, read it with a densitometer, and give you a suggested filter pack. Goodluck.
Celac.