Patience!!! That is the toughest ingredient you will have to have???
First,get a Flat, (that is a trimmed Brisket), the whole thing would wear your patience to Mich. and back.
These take time,and (IMHO),a low heat-225*to 250*. You will have to have a day when you can go out and check it from time to time.Do yourself a favor and get a Pen Thermometer(at grocers hanging on the little -'in your face '-hooks).
Put this in a little hole near the cooking grate,and monitor the heat.
A second thermometer(appox.$3ea.),to check the meat temp.
It will take at least one hour/pound of meat to cook it. Do not check the meat until you have reached the time factor-this guarantees it will be in long enough and unMESSED with, to let the heat get in the meat...i.e.-do not look!
After the time factor,you can check each 45min. to 1-1/2 hr.
keep it simple for spices-a litle Saly and Cracked Black Pepper is a good start.Put it on Just before the cook.
Patience is the answer for you,and you will give me points for this...
Hope thios helps and,