383 into 73 Dart Sport using exhaust manifolds

On the outside, sure. It does not have more room between the header and the block and the starter... :rolleyes:
The outside? Like standing outside of the car?

As a B body owner, the amount of real estate around the header under the car is far more roomy than the cramped quarters of the A body. Having been there and done that I assure you of this and the easier time you will have with these headers removing the starter from the B body vs the A bodies lack of room. Bank on that my friend. As a matter of fact, don’t bank on it, bet heavy on it. Real heavy.