First, remove the 8mm bolts closest to the lamps.
Second, using a 10mm socket or wrench carefully remove the nut from the posts. Do not lose them!
Third, disconnect the bulb sockets and remove the bulb. This step will make it far easier the accomplish the next.
Fourth, carefully pop out the marker light housings. They will require careful pushing and pulling so that you don't accidently damage the paint.
Fifth, each bulb is plug and play, test each one as you plug them into the socket. Do not twist the socket into the housing until after you have the marker light lined up with the posts in the holes.
Sixth, tighten the nuts on the posts and then reinstall the bolts for the fender lining.
Great instructions. Thanks. I also did this project and thought I'd add to a couple of the above steps.
For me, step two was time consuming for the rear lights. There isn't room to insert a rachet wrench over the nut on the post due to a metal body part next to it, so I used a 10mm open end wrench that has a slight offset. Attached is a pic of the old assembly with the nuts, one put back on and the other laying to the side. Note that while I'm talking about the rear side markers here, all four of them have the same posts and nuts.
Step four was also time consuming and somewhat difficult. The inner side of the marker light has a molded plastic tab that snaps into a clip fastened to the car body. In the picture above, the tab is next to the left-most post with the nut still on it. Note that the tab has a small button that might need to be depressed to assist getting the tab off of the inner bracket, or it might just come off with the right amount of force using the right tool. After removing the 10mm nuts from the posts, the bottom post will come out, but the top poar will come out only part way out. The clip grabs hold of the plastic tab entire assembly near the top. I used a trim tool to start prying it out (see pic below), but I ended up using a different trim tool that had "fingers" on the end to insert and pull at the clip location (see pics).
Like Twescaba said, be sure to hang on to those nuts that come off the plastic posts. They self-tap onto the posts of the new side markers.
Oh, and you might want to put a Band-Aid over your knuckles before you start the job, or maybe have someone pulling back on the fender liner to keep it out of your way while you work.
In all, it was a fun project, and it really dressed things up! (These pics were taken just after I finished the passenger side.)