Reinhart Rye help?

i want to make his rye meteil sandwich bread without a mother starter using a biga as suggested in the Whole Grain bread book. I can't follow whether you make a biga using rye instead of wheat? Make the wheat biga as printed in the whlole wheat bread recipe and only use a third cup in place of the MOTHER starter in the bread starter recipe?  using only a wheat biga in place of the starter as listed seems like it would get almost no rye flour into the bread. Anybody got any experience with this?  Or know a Peter Reinhart website or forum where I could ask the question?

Many thanks!