[going broke]

just bought a 2000 GT, need some help figuring out what is causing misfire on #1. Here is what we know about the car:
one owner before us, bought new, put supercharger on at 6,000 miles, kicked butt, ran up to about 40,000 miles, was going 120 on freeway slowed down into a stop sign, took off and has missed ever since. Took to Lone Star Performance in TX and they along with top 3 ford mechanics in TX worked on it for 6 months, switched and replaced everything except any wiring. motor has been gone through 3 times, we spoke with them and they claim it is nothing mechanical, has a demon in it. Our scanner comes up with engine misfire on #1, check engine light will come on, runs ok on bottom end, up over 3000rpm it starts cutting out and falling on its face, feels like the traction control is on but it does it no matter how you have the button, scanner also says its on even when we push the button to off, could this be faulty? Car shakes badly at higher rpm as well. The supercharger has been off since this started a year ago, we have 48000 miles on it, from what I have read on here crank sensors are #1 cause of misfires, we are trying that next, how would we tell if it has an aftermarket timing adjuster? Since it had a supercharger at one time would this be something that would have been added to the car that could be faulty? What is the correct timing for a stock 4.6 sohc? We plan on buying the supercharger from the previous owner and putting it back on the car when we get the misfire figured out. Any suggestion out there on what we should be trying? Thanks much