k frame question

Yes, I believe the front sway bar is mounted different however. Sounds like a fun project.

HOWEVER, the "Factory" big block Darts/Cuda's used a block specific to these cars and MOST blocks aren't drilled for the drivers side mounting bracket which is special to the 68/69 cars.

The sway bar mounting and steering linkage is all the same from 68-72. The only difference with 67 is the idler arm.

As for using a factory big block k-member in a non-original car. I would be against it for several reasons, but the biggest is that you can sell it for more than any other mouting solution will cost you and you will be helping to restore another rare car.