65 Barracuda engine swap

If the 273 had a 4 bbl intake, it is the HiPo or Commando engine, and very desireable, so don't just scrap it. A 360 is the cheapest power upgrade and bolts in except one motor bracket differs and you need an adpater ring to fit the crank tight to the torque converter of your tranny (don't try without it). Magnum 5.2 or 5.9L blocks fit the same as a 318 or 360 cu in, and gives cheap EFI and roller cam. If you use their tranny you also get an overdrive gear, but must cut the tranny tunnel to fit. Magnum heads fit an LA block and vice-versa. You can get alum intakes to use a carb w/ Magnum heads if scared of EFI. There are forums here for both Magnum and new Hemi swaps. A few have fit a GM LS engine, but never read of a Ford engine swap. The 1966- engine bays are narrower so not all engines and exhausts you see for later A's will fit yours. A 7.25" rear-end won't survive long behind a power upgrade.