I had a few on line but no longer. I guess I would refer you to this one: [EDIT: apparently direct linking is disabled on his website, bummer.}
Front Range bumper
It is a little hard to see, not being a side view, but note how he has tied in the lower frame crossmember with the upper captive nuts to which the original bumper mounted. That is the triangulation to which I was referring.

To get away with this, the front of the frame (below, rather weak) has to be stiffened significantly:
Before
Weak stock arrangement
After:
Beefy!

Not trying to be a commercial for Front Range, but he does have a good design. Friends have been very happy with his bumpers. Key is tying it into a strengthened frame crossmember.