These are my H3 not a H3T, hope that is ok.
You can get them with or without mud flaps. With flaps the other pieces have a recess molded in so the flaps will fit in there. I like the front flaps but on my H3 the rears seemed to drag on steep creek banks I cross regularly so I removed them. They are tough though and I added a couple of SS screws. Not sure how they would work in the rear on the T since your overhang is different.
So you can run the ones made for flaps without them but it leaves a little gap.
Be aware also they will change the lifted look but of course the wheels still go up in there.
I have installed and re-installed mine, a couple of times.
I put a thread in here when I modded mine to clear the 35's.
http://www.hummer4x4offroad.com/forum/showthread.php?376-Flares-E-amp-G-Hunner-Mod&p=6458#post6458
Your T of course will be a different in the back.
This is about the extra fasteners you may need.
I found some at NAPA that are Balkamp 655-2388. They are the short ones that can be used where there is only one layer of plastic. I later found some longer ones at a Crow-Burlingame "Car Color" store which is the auto body division. They are AutoBody Master PM48782. These are probably the best in most places unless you find they are too long in some areas and will not pull the layers up tight. They have two slots in the head of the insert so if after you push down the locking button if you need to remove it they have some special pliers that will pull it up. Even with these you usually destroy them getting them out. The old school method is a flat blade screw driver, needle nose and side cutters. They will wear your thumb out putting them in. I used a dead blow plastic hammer on the ones I could get to. They package says they are for a Chrysler but my H3 doesn't care.
These are my weapons of choice.
This is the flare designed for a flap in the rear but with it removed. So deciding ahead of time if you do not want the flares will eliminate this gap.
front flap
Hope that helps you decide.