Description is a bit vague... Are you not able to install the torsion bar because of header interferance? Are you trying to move the motor and K-frame to affect header position?

I've got a stock K-frame, TTI headers, and motor plate with good clearances so I too am wondering about the after market K-frame alignment.

B Dartman's 71 Dart Swinger in Mopar Muscle (Sold Dec 2021): https://www.hotrod.com/articles/1971-dodge-dart-destiny-determination/
B Dartman's 71 Dart Swinger in Dodge Garage (Sold Dec 2021): https://www.dodgegarage.com/news/article/showcase/2019/04/destiny-determination.html
B Dartman's 71 Dart Swinger early build pictures (Sold Dec 2021): https://s165.photobucket.com/user/Billswild440dart/library/