Is this a regular front brush guard? If so, you just need, I think its 13mm wrench and ratchet, and you can remove the four bolts holding your current bumper to the frame rails, then slide the brush guard prongs onto the regular bumper area (where you just took the bolts out of). Then put the bolts back on...that should be it, you might need to trim the plastic valence/air deflector on the bottom of the bumper. At least, this is how I think its done on the D1 at least. Crawl under the front end, its really much easier than it seems, the usual brush guards are not very sturdy when installed because of the fact that the only place they are secured are the four bolts areas.
Its hard to explain, but the brush guard prongs will sit on the outside of the regular bumper prongs...I swear tho, if you just get up under the big girl, you will see where everything goes...