Ron_L will never steer you wrong.
Since this is your first I say just use a rub you like and forego the injection, if you feel you need/want something different then try that next time. If you try 12 different things the first time out and you don't like the end product you won't really know which of the 12 things threw you off.
Start your fire, rub your meat, and wait it out. Enjoy and good luck.
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