i am going to replace the exhaust on a 91 240 from the cat on back (both mufflers, axle pipe and tail pipe.

while down there, im gonna change two other gaskets; the exh manifold to exh header pipe gasket and exh header pipe to cat gasket.

my exhaust manifold has two exhports that lead to the exh header pipe inlet. The exh header pipe has reduces those two ports so that there is only one exh port into the cat.

my question is, i can see that there is a flat gasket (with 3 bolt holes)between the exh manifold and exh header pipe, but is there also a "donut" in each of the exh ports?

same question for the exh header pipe to cat?

thanks for your help