I found this...
----------------Qty
GM Part No.-----Needed-------Description
Engine Protection
15203366--------1------------SHIELD,ENG CK1
11518341--------4------------ BOLT,HEX,M10X1.5X25,14 THD,28 OD,6202M,7114M,TAP,TR-PT(ENG SHLD)
15745156--------1------------ SHIELD, ENG CK2,3
11518341--------4------------ BOLT,HEX,M10X1.5X25,14 THD,28 OD,6202M,7114M,TAP,TR-PT(ENG SHLD)
I can only assume that "CK1" means "C1500" or "K1500" and "CK2,3" means "C2500" and so on...
If so, your 1500 might need part number 15203366 instead. I'd call dealer to make sure, though.