JBA p/n 6610S headers are designed to fit ‘64-1/2 - ‘70 289/302 (not Boss) Mustangs equipped with 4 spd manual or C3/C4 automatic transmissions. These headers are not designed for 5spd applications. These headers provide significant increases in torque and horsepower throughout the RPM range and allow for maximum ground clearance. To help make sure you choose the correct headers, h-pipe and exhaust for your Mustang please refer to the chart below. If you still have questions, give us a call. Stainless steel finish