How to Install BBK Chrome Equal Length Shorty Headers on your 1986-1993 Mustang 5.0L

Step 1 Disconnect the negative battery terminal and place front of vehicle securely on jackstands.
! CAUTION !
Use extreme caution under vehicle
Step 2 Remove hose clamp at throttle body, unplug mass-air sensor, and remove 2 screws holding top of airbox and sensor bracket from the front of strut tower then remove entire assembly from vehicle.
Step 3 Remove air-injection routing tubes by disconnecting the 2 vacuum lines at the diverter valves, remove the hose clamps from the back of the air-pump and remove the 2 clamps connecting the hoses to the steel lines (near rear of valve cover) and remove entire assembly.
Step 4 Remove all spark plugs and the dipstick tube.
Step 5 Working from under the vehicle (use caution) remove the nuts connecting the h-pipe to the exhaust manifolds and tailpipes then slide the h-pipe backward a few inches to gain clearance for the header installation.
Step 6 Remove the stock headers and clean any gasket material from the gasket surface on cylinder head (header removal is from the inside of the engine compartment).
Step 7 Before reinstalling, the dipstick will require clearancing (shown in Photo A).
Step 8 ! CAUTION !
Use extreme caution under vehicle and raising motor
To avoid damage to header coating or paint in engine compartment it may be necessary to raise the right side of the motor while installing passenger side header. The motormount is connected to the car with 1 nut, easily accessible from under front of vehicle. (See Photo B).
Step 9 Remove nut and jack motor up using a floorjack or hoist being sure to place jack as not to damage or harm any
part of the engine. Once motor is in raised position place an appropriately sized block of wood between motormount and frame (this will hold motor in upward position in the event of jack or hoist failure).
Step 10 Set header in place and start all bolts by hand, then lower motor back into position in frame, tightening the mount nut to factory specification. Torque all header bolts to specification.
Step 11 Reinstall the spark plugs and wires.
Step 12 Before reinstallation, the air-injection tubes must be modified as shown in Photo C, using hose and clamps provided in kit.