Assuming your 99 is like the older DS's, there really isn't too much to it. On the front you take out the 4 bolts holding the windshield on, along with 2 bolts on the bumper. Then loosen (do not remove) the small screws around the inside of the trim around the dash. That should be it. On the rear there's 2 bolts behind where your feet would be when driving, 2 in the bagwell area, and 4 that hold the seat backs to the frame/body. Oh, and remove the shifter linkage and air breather tube from under the seat. That's it! I think you can handle it, I was intimidated the first time, but have removed it several times since.
Jason