Not sure if you are still looking for a turbo kit. I will be coming into some money and I am kicking around the idea of a rebuild and turbo kit on my 99 with the 4.6. Here is a link that might help. Has everything from headers to the stuff for the computer in the kit. Total Performance Complete Street Turbo Kit: 97-03 Ford Truck/SUV w/4.6 & 5.4L (air/air intercooled)