Cylinder Head number: *619, *770 *= last digits Aprox. Year: 1990-2004 1 piece rear seal crankshaft Remanufactured Cylinder Head 3.0l 1990-04 #17 for General Motors
Cylinder Head number: *772, *140 Aprox. Year: 1996-1999 Roller cam engine with balance shaft 10224542. Has 6 bolt timing cover, 10 bolt oil pan rail and 8 in intake manifold. 175 & 205 hp aprox.
Cylinder Head number: *113 Aprox. Year: 2000-2009 Roller cam engine with balance shaft. Has roller rocker casting. Has 6 bolt timing cover and 8 bolt intake manifold.
Cylinder Head number: *279 Aprox. Year: 1996-1999 1 piece rear main seal. Roller cam engine. Gen VI, 6 bolt timing cover. Electric fuel pump. 330 hp aprox.
Cylinder Head number: *193, *083, *217 Aprox. Year: 1988-1995 1 piece rear main seal. Valve covers bolt down center. 2 bolt main. Has metal timing cover. 12 bolt intake. 260 hp aprox.
Cylinder Head number: *193, *083, *217 Aprox. Year: 1995-1999 1 piece rear main seal. Roller cam. 6 bolt timing cover plastic. Mechanical or electric fuel pump. 12 bolt intake. 260 hp aprox.
Cylinder Head number: *906, *062 Aprox. Year: 1996-2012 1 piece rear main seal. 6 bolt timing cover plastic. 8 bolt intake. Mechanical or electric fuel pump. 260 hp aprox. Vortec model.