This harness is standalone and is not intended to replace the OEM engine wiring. Standalone harnesses are intended to run the designated engine & transmission only, generally when swapped into another vehicle. This harness is designed for the 1997-2004 throttle by wire LS1/LS6 engines with a 4L60E/4L65E automatic or T56 manual transmission. These engines were factory equipped in 1997-2004 Corvette. Harnesses do not include any emissions related connections. Included with this harness is an 8-circuit modular fuse block and GM color coded wires with labels for easy installation. This standard length harness allows four feet from the back of the intake manifold to where the fuse block and ECM mount. . . perfect for those that plan to mount these components under the dash or in the glove box. This kit includes: All new fuel injection harness with OEM fitment connectors and harness breakouts; OBDII connector, mounting bracket and check engine light; Rubber grommet & mounting hardware. This harness also requires the following mating parts; ECM #12200411; TAC Module #12578953; Accelerator Pedal #12565643. PLEASE NOTE: GM no longer offers the accelerator pedal #12565643. The sensor is still available, however, the full assembly is not. We recommend sourcing a pedal before proceeding with your project. We suggest trying a certified used parts supplier. We recommend checking the online manual for the full list of required mating parts prior to ordering.