Omit book intro in secondary project of diglot

Question

We are typesetting a diglot project using PTXPrint, and the primary project has book introductions but the secondary project does not (nor are they desired for the secondary). Rather than having the right-hand side of the intro blank, we would like to have the book intro of the primary text full-page width, as it is when printing a monoglot project. Any ideas on how to accomplish this with PTXPrint? We did it once before in a PA/InDesign job by manually adjusting the intro frames for each book in ID, but that's not an option for PTXPrint. Is there any way of switching to full-width mode and back again? Or other suggestions?