To do this effectively you have to very much over expose the film and then
give it a very short development in a paper developer diluted to about 1 :
20 for Ilford's Universal.
Unless red plays a very significant role in the composition of the the
original, the blue sensitive nature of the film should not make that much
difference. Ordinarly one would not expect red to record on the film so
that red items in the transparency would appear black if printed onto