Also, if you're using the chrome trim on the extensions, I believe those are different, as far as how they attach and depth too, maybe.The 1970 Dart fender interchanges with both a 71 Dart and a 71 Demon. The 1972 fenders use essentially the same stamping but the side marker lights were changed. Physically they will fit.
The brightwork trim on the fender extensions and hood edge must have been an option for both years.
Dart and Demon fenders are the same for a given year. 70/71 are the same, '72 has the 72+ plastic marker lights that are in a totally different location from '70/71.
The fenders are actually not the same overall either, at some point in '72 the wheel opening was made longer. This makes '72 fenders shorter along the bottom of the front section of fender and in the dog leg, which gives extra tire clearance especially in the front (there was already plenty in the back. Basically the front of the wheel opening has a more gradual curve in '72 that gives the wheel more room (~1"). The dimension differences are listed here
Holeee crap, I never noticed that until you pointed it out and at first, I called bullshit.
Then I looked....
View attachment 1716328873
The arch forward of the tire comes almost to a plumb line in the 70-71. Below is a 1976 Dart.
View attachment 1716328874
You can see how the curve of the opening at the front ends at the bottom with some forward angle to it. The early fender is nearly plumb/straight up and down.
I love learning new things!
You remind me of something, when i did body work on my 70 Dart the reR WHEEL WELL LIPS HAD BEEN FLATTENED, AND THE FROBT FENDERS EACAH HAD A "SLIVER" REMOVED FROM THE FRONT SIDE OF THE OPENINGS. I had fixed the rear wheel lips and grafted in patches on the fenders . i suspect someone had ran different size wheels/tires and these mods needed to be made on the car. I now realize through trial and error not many wheel choices especially on the rear and I have the 14 inch ralleys with 205 70 14 tires. That will be ok to cruise I think . Sorry hit caps lock not shouting...Right?
Honestly you can see I was skeptical in the thread I linked, but then I realized I had a few of each 70/71 and '72 so I just measured. I don't know exactly when the change over occurred, you'd think it was probably at the same time as then side marker change but with Ma Mopar you never know.
Either way the 72+ fenders have a longer wheel opening, which makes the tire clearance at the lower front corner easier on those cars. If I ever paint my car I will take a "pie" out of that lower front fender to match the '72 measurements and grab some extra clearance on my 275's. They don't rub as it is but they definitely don't have much extra if I ever went to a slightly taller tire.
This thread has more measurements in it, the OP had a '72 with one fender of each type of wheel opening on his car. Didn't get a reply on whether both fenders appeared original, but the front section on the '70/71 fenders is 8" long where the '72+ fenders are like 7.25". The rear dog leg also got 1" narrower on the 72+ cars. Also worth noting is that the AMD reproduction fenders seem to match the later, longer opening. I can't seem to find the thread where I got that info though.
Help: 72 Dart Swinger front pass. fender rubbing
The front change is really helpful, the rear one just kind of exposes more of wheel well and corner of the chassis which doesn't actually look as good IMO.