There's only one reason that the cudas went back to two headlamps in 72. Cost.
In 72 they decided to bring cost down in every way possible on most every mopar built. On the cudas, they eliminated the very expensive 21 piece cuda grille, two of the headlamps and the associated hardware, the gills, gaskets and retainers, the expensive multi piece side markers, the expensive turn signals, the expensive tail lamps and many other items. They eliminated almost all of the options that were available in 71 as well. No more convert, no more Gran Coupe, no shaker hood and multi piece shaker setup, no rear spoiler, no louvers, no leather and on and on and on.
In 72 they had just the two headlamps, the three piece grille plus two plastic headlamp rings, cheapy one piece side markers, turn signals cast as part of the valance insert, cheap plastic turn signal bezels, cheap plastic tail lamps and on and on and on. The bonus was they shaved a little weight off to make up for the bumper impact bars.
I own several of each body style and I love them all. I'm partial to my 71's but the 70's are nice as well. I'm down to one 73, but wouldn't sell it unless someone offered big bucks.
The 70's exude "muscle", the 71's portray "elegant muscle" and the 72-74's say sporty yet economical. They are truly three different versions of my favorite body style.
