I just did this so have a couple of comments.

First, some of the bolt size references were different on my car, but all are either of the two sizes referenced.

Second, and more important, you don't have to move any accessories to remove the headlights if you (a) remove the bumper, and (b) remove the two screws under the headlights along with the two at the top front. There is a slide-in plastic bracket that bolts in at the front under the headlamp, it has the two rear bolts that are mentioned in the OP but those won't need to be removed if you take out the front ones. If you do remove the back bolts and leave that bracket installed, when you slide the headlamp assy back in you'll need to be sure the slots on the headlamp assy mate properly with the tabs on that bracket.

There is a reason I know about this bracket - I had to replace mine after breaking off one of the rear tabs when trying to replace bulbs/exciters without taking off the bumper. See, I got to do it both ways!

FWIW I just used a large cardboard box to rest the bumper on while doing the headlamp work - it only needs to drop about an inch and move forward to do all the work. And as others have already commented, the bumper removal is easy.

Now I have to source the bolt that was stripped (fender well) and the screw for the fog light that was missing - not the first time this bumper has been off!

2005 4.8is