65 barracuda with 340.. What heads? What Headers?

Build your own headers. I believe you can just add washers to one motor mount and will bolt in fine. Biggest thing is bellhousing. You should upgrade to the larger bell. The stock 9.5 clutches are not the stoutest. I have a 10 inch and pressure plate on the stock flywheel that was custom built. When or if you do upgrade to larger clutch setup you'll loose room for headers even more so. Not sure what headers fit with larger bell housing.

Early barracudas all up the west coast. Haha