5.4L DOHC in to a 2001 GT HELP!

One mentioned tweaking the booster. You cannot. You have to go hydroboost. The hydroboost works on the 4.6L 2V and 4V. It also works on the 5.4L 2V. I am not sure about the 5.4L 4V. If a 5.4L 4V is wider than a 4.6L 4V, than I would say one would be pushing it. If it won't fit, you have to use manual brakes.