Headers won’t fit in 67 440 dart

You're over compensating. Put the K Frame and the front suspension in the car, then mount the 440.
It takes alot of tweaking and header pinging to fit 440 2" headers into a A-Body. Get a propane torch and a heavy gauge hammer, cuz you gonna be pinging those TTIs. The member had a great point about your trans not being lined up.
Your engine must not be tilted...do whatever you have to do to level it. Build shims out of aluminum (Ace Hardware), if you have to.

Playing Mark Worman and lifting the car body onto a big block in an A-Body is not the way to go for a first time build (here comes to member outrage to that statement). All the Worman stuff you see on TV has been previously orchestrated.
And you wanna do this in a weekend.

What puzzles me is how can 2 A-Body K Frames be different?

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