I was trial fitting the H-pipe last night,and noticed the old style hard fiber manifold gasket they give you. Those don't give a good seal over the long haul. Some folks say they reuse the original factory "O" ring gasket,but there isn't much sealing area left with the larger 2/1/2 inch flange opening. So I will try what has worked on my header collectors,on my 85 LX. I make up a copper O ring,that will offer some seal crush and high temp sealing. Other than that looks like all will fit OK. Keep you posted.