1. Installation hardware is not included in this kit and can be purchased at any local hardware store. Adjustment slots are predrilled and customers can customize placement on bottom of bumper to extend as far as they wish although it is made to sit flush with rear of bumper.
2. Removing front bumper may not be necessary, but it is advised to make the job easier, removal of from bumper can be done it roughly (20 minutes) and will help with the quality and placement of the finished product. See instructions on bumper removal here. http://www.g8board.com/forums/showthread.php?t=19042
3. Does require installation of nuts/bolts in rear of bumper (as there is no place there on the stock bumper to mount to.)
4. Spacers are provided for between the bumper and splitter where the stock bumper cuts in and upward. You may not wish to do this, but it is an option, depends on how you want the finished product to look.
5. I would rate the difficulty of this project a 2 (from 1-5) as it is pretty straight forward.