Speaking of manifolds, I would like to see someone try a 99+ equal length manifold adapted to a carburetor. I feel that would have the best chance of flowing fuel evenly. Plus you get away from the 4.0 efi system limitations if you use the Fitech GO Efi system. But in the end you’ll still be spending much more for a marginal outcome then just by jamming a 5.3, 6.0 or 6.2 in it.