The 18 GT Manifold swap is a great bolt on modification for 11-17 Mustang GT, and 11-20 F150 5.0L. As seen on Matt's 2018 F150 5.0L, the manifold made a huge difference and really helps wake up the top end on the F150. On 2018+ F150 5.0L the 18 manifold is bolt on besides drilling for a map sensor and modifying the passenger side pcv hose(or use a catch can). The IMRC and vacuum lines are all plug and play.
For 15-17 5.0L Mustang GT and 15-17 F150 5.0L the manifold can be installed with IMRC delete or with IMRC wiring conversion harness.
For 11-14 Mustang GT 5.0L and 11-14 F150 5.0L the manifold can be installed with IMRC delete using MMR lockout or zipties.
Install Notes 18+ F150 5.0L:
18+ F150 4WD: The vacuum harness is a direct plug and play and 4WD doesn’t make a difference. 2WD is the same plug and play. The evap line also plugs in with no issue.
Hardest part of the install(not very hard) is unplugging the manifold and getting the factory harness tabs off the stock manifold. Remember 3 imrc plugs and 1 map sensor plug. The map sensor plug has a white tab that needs to be pushed out and then you push it in. (Like 11-17 coyote coil plugs)
The wire to the plug on the evap is a little tight so I cut a small portion of the tape on the harness to give it more slack.
The MAP sensor is easy to install. Shave off the plastic tab where the harness would normally push into. Shave the plastic grooves flat. Pick a place to mount the map sensor. Drill a hole and use the stock manifold for reference. Use a self taper to secure the map sensor and I like to use rtv to ensure it seals around the sensor. I ended up using the factor bolt in place of the self taper because I tightened the self taper too much.
IMRC is direct plug and play.
If you have a catch can you will not need to worry about this but on the passenger side pcv hose it will not fit. Either get a catch can or make your own pcv line by cutting the plastic factor line and use a rubber or other hose in between the two pcv fittings.