* K1500: Will have a chassis code beginning with "CK" (for 2WD) or "RK" (for 4WD).
* C1500: Will have a chassis code beginning with "CC" (for 2WD) or "RC" (for 4WD).
If the sticker is missing or illegible, you can also try checking the title or registration documents. These sometimes list the chassis code or may specify "K1500" or "C1500" directly.