First off...WELCOME!

Always good to have members from over seas.
Don't worry to much about your english, we might give you a hard time but we are just kidding around...All in good fun.
Shawn F. is right, The front is easy if you just want 2.5"-3". Doing stuff with the springs is a bad Idea (if you want to DRIVE it low) if you want to just have it low for the show then you could put air bags on the front and just air them up to the propper height to drive.
If you want low there are some options. A lot of guys are putting the trucks on Crown Victoria frames (crown vic, or CV) this involves a lot of body work and welding to the body. Others have put Aerostar IFS (Frod Minivan) on with a small amount of welding, this is not a bad option, I just don't know if the Aerostar springs can take the weight of the FE. I am going with a Dodge Dakota (pickup) IFS that one of the members here (
ELpolacko) makes a weld in crossmember for. You can also go the Mustang II rought. (car, very common) if you do you should go through
Fat Man they have the proper geometry and stiffness to work with these heavy trucks.
Like shawn said...the back is WIDE OPEN!
Good Luck and we love to see pictures!!