Item Part Description Quantity Variation Number 5120 1 GM91951 Cylinder Head 1 2 GM88786 Retainer 48 3 GM46673 Cap 24 4 GM46683 Sleeve 6 5 GM49845 Spring 24 6 GM50041 Seal 24 7 GM49906 Bushing 2 8 GM49886 O-ring 7 9 GM18873 Pipe plug 1 10 GM88785 Valve Seat Insert 12 11 GM88784 Valve Seat Insert 12 12 GM88799 Valve Kit 12 13 GM49841 Valve Kit (Intake) 12 14 223448 CAP 4 15 GM49860 Sleeve 6 16 GM88698 Cap Screw 26 17 360094 Gasket, Cylinder Head 1