273 Commando Exhaust Question

I thought there used to be an article on FABO’s “”How to” forum that showed how to do this using a front valance/splash shield from a ‘65 Dart. I just went through all the articles there and couldn’t find it, so it’s possible that I saw it somewhere else. I’m bummed, because I had planned to use it on my GoGo coupe. The original rear panel With the cutout on it was replaced during an old crash damage repair. My 235hp 65 convertible still has its’ original panel and I plan to use it for reference. As I recall, the article used the cutouts from a front pan welded in the rear. Sorry I lost track of it.
I remember seeing that as well for a 65. 66 has no valance.