Cooking on Gas Grill, What do I have to change in my technique?

Tonight I cooked pork chops in my favorite skillet and they came out perfectly as usual. Two weeks ago, I tried cooking them on a gas grill for the first time and it was an unmitigated failure. Dry and overcooked despite my hovering about with the thermometer. Heretofore, I was a charcoal kind of guy and really wanted to buy an egg this time when we bought the grill. This idea was vetoed by the Wife Unit (the boss) and we got a gas grill. How or what do I need to adjust to cooking on a gas grill as opposed to cooking over charcoal, or on the stove for that matter?