Mark Erce,

Hi.....correct part number is:-

A-ST-020 ARROW RACING GTR-21 HEAD GASKET SET (4PCS)
2 cooper gaskets, 2 silver gaskets ( Metal Headshim )

A-NB-112 ARROW RACING GTR-21 EXHAUST SEAL/GASKET SET (4)
This is the rubber gasket for your engine and tune pipe.

Hope this help.