69 Barracuda Hemi swap

You might as well do the 392 now. If you do the 5.7 you will have to get a different wiring harness and computer. Also depending on your suspension k frame etc your headers may be different. And if you change transmission harness and ECM will be different. Also if you get a truck 5.7 and switch to a 392 you will have to get a different radiator as the inlet and outlet are different.