Just went back thru all my bills and no go, so checked all my books and nothing so remember I did try 3 sets but then found out by going thru all the Hooker application guide that they dropped the one set, only one set avail, coated or not so 2 diff part #'s but same header and has the collector length that is 10" so only works on a 2wd, not a 4wd even though it is listed as 4wd, just to tight to turn up to transfercase on pass side only. Maybe see if the Chevelle set mentioned will be a better fit, I did look Chevelle up too and they are also a 10" collector length..
So now I am confused. I did notice on the I believe Summit site Hooker makes a free flowing cast exh manifold, not sure if for your appl, prob high hopes. Good luck, let us know if you figure it out.