Gen lll hemi install in a 67 barracuda

Mopar Action has a number of articles on this swap in Apr-Oct 2023. There are a number of clearance issues to address including alternator and oil filter. Holley has a solution, but there are others as well. Also see: Gallery: The Ultimate A-Body G3 Hemi Swap Guide with Project Orange Crush - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech

and many other sources.
Best of luck. I understand that some 3G's need the motor moved forward by a small amount that leads to many other fitment issues.