no worries, thanks for adding the pics. Yes, looks like you have one of the Y pipes in the pile. I believe one goes through the firewall straight and the other goes through and curves. I can call you tomorrow if its easier.
here are some pics of what i am looking for, my 74 doesnt have a rear heater. I would like to add heat to the rear eventually. No hurries, enjoy your dinner. I can call and leave a message tomorrow.