Install for me has been straight forward so far. The drivers side manifold flange needed some light touch up/grinding to line up perfectly with the head. No biggy. Passenger side was perfect. Waiting on the spacer for the drivers side as shown in pic above. New cast manifolds are sweet. Some will say, and I agree, why not fix the need for a spacer in the new design? They should have, but it is nice to see the company invest in making a better product with the cast version.