Not my GMT, but I fixed a headlight on a neighbor's 07 TB. (Dirtbag husband up and left her high and dry with, among other things, no clue how to take care of a vehicle.
)
So I check the right low beam fuse, and find it looks melted. (I also note it's a cheap aftermarket fuse) Carefully I wiggle it and try to remove it, and one leg sticks in the fuse box. Not to worry, I get my trusty needle nose pliers and gently grasp the protruding leg, which proceeds to break off flush with the fuse plug in.
At this point, I tried digging it out with a small pointy object, and still no go, the darn thing WILL NOT come out. Next step: borrow it from her and bring it to my garage to work on where I have access to all my tools. Now unhook the battery and take a GOOD pic of the fuse box, and remove all the fuses. Next step is to unscrew the 4 bolts sticking down through the fuse box bottom, (the ones the black plastic thing hooks over) these don't unscrew all the way, and they stay in the hole. Now the box can be lifted off of its perch if you work loose the clips at the base. Next step involves cursing while realizing you forgot to unhook the megafuse wire connections, and then removing them. Now you have a fuse box panel in your hands that looks like it should just pry right apart for you to clear the obstruction out from the backside, right? WRONG!!! Now you have to, after 10 minutes of head scratching and more cursing, tap the bolts out from the bottom side with a small hammer, then get a drill bit of just large enough size to remove the flare from the bottom side of the bolt insert so that the halves of the box will separate. Once the four inserts are de-flared and removed, the halves will come apart and the pin board sandwiched in the middle will come out also. FINALLY you can remove the broken little
$%&*@#% of a cheap fuse leg by pushing it out with a small screwdriver. Reassembly, as they say, is the reverse of removal. You need not worry now about the flares on the inserts you drilled that held the thing together, because when you re-bolt the thing down (you're actually bolting it to several large connectors, think PCM connector) the bolts will keep it drawn together plus it snaps down back into the vehicle. Now use the pic you took of the fuse box with your phone to put all the fuses back, and hook the battery back up. Last step is to return the vehicle to your neighbor and when she frets about paying you for all your work simply reply "Really, it was a simple fix, don't worry about it!"
BTW: I should have taken pics I know, but I didn't cause I was too worried about royally screwing up my neighbor's only ride, plus I was kinda hurrying to get it back to her.