If "we" can all remember back to August 1994, The Cuss was hunting for a Cab Plus B2200 like 1988-1990 so his kids could sit in the back seats. I found a 1988 Cab Plus with 50K miles and put my $5K down. It had a dent on the front bumper, right next to where the front license plate would be.
Jump ahead to August 2012, and my youngest daughter is now 21.5 and bought her own first vehicle ('98 Pathfinder), which needed a front bumper. So I finally bit and ordered a bumper from the same dealer as her parts.
First parking lights and turn signal lights come off and get disconnected. Then grille (3 hidden screws in the honeycomb matrix). The four big 17mm head bolts. After that the lower bumper grille (plastic) and the side pieces unbolt. I got to clean off the AC condenser while the stuff was off, a fair amount of bees (maybe because I drive through Bumble Bee, Arizona ?).
It turned out (as most of my recent jobs have been) a bigger pain in the $%&&$#%^&%##%& butt than I would've expected. The bumper itself was nice enough, put the punched square holes were about 8mm, and the original carriage bolts had 10mm squares, so didn't fit, grrr !!! So rather than file down the seven which would've needed that, I went to Home Depot and bought SAE carriage bolts 1 inch x 5/16 thread, which had a 5/16 square part (17 cents each) plus washers and nuts for those.
So it turned out OK, and good practice for when I do daughter's Pathfinder bumper. And one of my side pieces was a little loose, so I was able to add a washer to tighten that up.
Edit: if you buy a new old stock front bumper likely your existing hardware will all line up.