I would, and have, buy a good set of multi piece race headers and install them in the car, piece of cake scope up
You may, probably will have to, remove the drag ling under the oil pan and pitman and idler arm and lay it out of the way until your done with the headers wrench twocents up

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)