1965 Barracuda- Restomod
# 1 the T5 will not hold up to that motor your 5.7 unless you drive it like it was your grand mother driving it,,there are up graded gear sets for those trannys, and will cost you around 2500 when finished,,,and still not a bullet proof trans with that motor if you have a decent rear tire,,,
as for the 1972 K frame the 1967 and up A bodies are 1 1/2 inches wider in the frame rail area compared to the 1966 and older,,,ide like to see pics of that 72 K frame bolted in to your early A,,,