Problems,66 Dart manual steering coupler

I,ve changed my p.steering to manual,swapped the column(which has no rag joint)power one is to small.What have you guys used?Flaming river has a u-joint coupler part#FR1506M $177.45 for manual or the straight adapter for $35.Which have you used?My car has a 360 and am putting Spitfire headers on.Thanks for any help!