There was one guy, Don Foreman, in the northwest division that ran a 1200 Civic in ITD. Some divisions recognize the D class. I am not sure what he is running now. He tried to convert it to H-Production about the time the Club Racing Board bumped it to G-Production. You can find him on the 1stgencivic.com forum. I hope this helps.
Have you tried to contact former HP National Champion, Adam Malley? He's a good guy, own's his own shop, so daytime is limited for conversations about racing. He's in Conyers, GA