I wonder if fitment is different because you used a slant six k-frame? I've heard other members having to shim their motors and grind on the manifolds to keep them away from the steering box/shaft.
Did you make a build thread? I am curious to see how the magnums fit when they are flipped. Do you have power steering? And I love the look of the build!
Wow i love to see an original owner driving their car like they did when it was new, no trailer queens or show car crap. Just workin the shifter and tearing up asphalt! Tomorrow i'm gonna take my duster out for a "spirited" drive!