putting a ford 5.0 in a 72 Dart

Not exactly what I was asking about.
First of all, welcome to the site.
I guess by now you have figured out that most of us are a bit touchy about that. As mentioned by A/JFormS and RustyRatRod below, putting a Coyote engine in an A Body will be a monumental task. MONUMENTAL! The Coyote engine is an amazing engine. I can certainly understand your interest. However, you would run into dozens of problems that would require an expert fabricator, welder and mechanic. If you tackle something like this yourself, you better be really good at these tasks. If you pay to have it done, I hope you have DEEP pockets. Either way it will be a money pit. I understand wanting a modern, powerful engine. The Coyote is a very wide engine. I doubt it would fit without major surgery. I have a few suggestions. For a fraction of what it would cost to get the Coyote in there, you could:
1. Bump the 318 up to 350-375HP easily and add then modern fuel injection. The Holley Sniper unit with their ignition and a new fuel tank with a built in fuel pump would make the engine highly efficient. It would start, run and perform like a modern engine. The LA 318 is an AWESOME engine. Just ask @318willrun. I bet he has lots of stories about putting FI on a 318. PLUS, the 318 is already there. NO fabrication required. Just have it rebuilt to your desired specs (make sure you go with a roller cam) and then add the FI stuff. It would be a fantastic car, cost WAY less that the Coyote swap and be a very easy build.
2. Put in a modern Chrysler Hemi. That has been done a lot. You would have a large, built in support group here on this forum. Not only has it been done a lot, but there are also aftermarket parts available to help with the swap. It would be a great way to get modern EFI and power. Plus, if someone said, "Has it got a Hemi?", you can say YES.
3. Contact Blueprint Engines and ask about a stroked small block Mopar with FI. I bet they could hook you up with one that was ready to start and run. Blueprint is a sponsor on this forum, and they take really good care of us.

To be honest, I would recommend souping up your 318 with the Holley Sniper unit with their ignition and a new fuel tank with a built-in fuel pump. A 318 with 350-375 HP would be a fast little car that would be fun to drive and do wicked burnouts. A stroked small block could easily have a hundred more horsepower.

Let us know what you decide to do. Remember, it is your car, and you can do whatever you want with it.
Not to be rude, but that's a money-pit idea.
After the engine and trans are in and running and tuned, the rearend will need to go, new tires and wheels, upgraded suspension/steering/ and brakes. Then there's frame connectors, a 4-Link, and CalTracs. Then there is the hiway rpm, the hiway wind and body noises, and NVH (Noise/vibration/and harshness.)
Two years later, you got a 50Plus yo Dart-shaped Mustang, that nobody will ride-along with you in, cuz it rides like a truck..... and the worst of it is, you could have actually bought the Mustang for less, which will always have resale value, whereas the FrankenDarStang is yours forever..... lol
Jus saying.

Those engines are pretty wide with the 4 valve heads. The 72 Dart is wider than the pre 67 cars, so you have that going for you. Just measure, measure, measure. I'm just guessing, but I bet it'll fit. Ain't but one way to find out.