340 stock manifold to header adapter question

Now I see what your needing to do! You could see if an exhaust shop has some 2 1/4" two hole flanges that will bolt to your manifolds, and get them to weld you a piece of pipe to them in a way that you could hook to them. Places that do exhaust work always have stuff like that in a scrap pile. You could take an exhaust manifold with you to see if they have something to match. I think (?) the flanges are the same on both drivers and passenger sides of the manifolds.