NO WATER in the water pan. Fill it with clean sandbox sand you can get a Home Depot or other such place and cover the sand with heavy duty foil. Put one of those disposable aluminum foil pans under the turkey to catch the drippings. Yes 2-3 shot glasses of chips every 30-45 minutes will work if you do not have or want the AMNPS. But the AMNPS and MES were made for each other. Otherwise you will be adding chips quite frequently and that's ok. Remember Hickory, Mesquite are very strong flavors so if you are using one of those, cut them by adding some fruitwood (apple, peach, cherry etc).
We have a MES at work and I find that with the water in the pan makes it very humid and will cause issues getting a crisp skin. The use of the playground sand will create a heat mass to help with even cooking. Catching of the drippings is good for gravy. I would add a sliced onion, a couple carrots and a stalk or two of celery to the pan during the smoke. After the smoke while the turkey is resting use the pan drippings and vegetables to make a nice gravy with.
So to brine or not to brine........ It is really a personal choice
Make sure you have an accurate thermometer for chamber and food temps. Our MES is not very accurate for temps.
Temperature to cook at. 225 is traditional low and slow. I start out low and slow till the meat hits 140, then I will turn it up to 300 till the meat hit 165 IT in breast and 175 in the thighs.
Time of cook..... I find that it goes about 45-60 min per pound, but it can vary with each cook.
Let the meat rest for an hour....
Enjoy .........