Don't have a diagram, but could tell you where the bumper's parts are.
Can't tell you the sizes though, I can't remember what they are.
First off, remove the bottom, black splash guard that is hooked to the subframe and bumper cover. Mine got removed for me when I hit a really big puddle. :p There are the two little clips (one per side) between the headlamps and the grille. There are two bolts connecting the bumpercover to the fender. I have found that it is easier to remove those if you have a lot of extensions, and the bottom splash guard is off. Also, remove the wheelwell splash guards. There will also be a support brace going from the radiator support (IIRC) to the bumper cover. That on the bottom, directly in front of the tires.
If you have fog lamps, disconnect their power leads before you try to remove the bumper cover. :p
I think that about covers all of the bumper cover parts.
If you can get to them, soak them in WD40, trans fluid or something like that and get to them later. The trans fluid worked for me when I was trying to free up some rusty, STOCK, u-joints on the `80. They popped right out, where before the 12-ton press didn't even want to touch them.
EDIT: Take your grille off too. It would make it easier to remove the bumper. When the bumper cover is free, tilt the back end of it downwards slightly. There are alignment tabs that that will hang up on your fenders.
