Exhaust manifold for 318 swap in 63 valiant

Better off with the 318 manifold than the 340. The problem with the Early A is not clearance at the steering column, it's how the head pipe has to fit between the framerail and torsion bar. Early A manifolds are the same as the later ones except their dump point. Early manifolds point straight back, later ones down and outward.
A good exhaust guy can make the later manifold work, but it is a tricky, tight squeeze.