I remove silvery membrane, cut the tapered ends half way through and fold them over, then tie them like you would a roast. This keeps them the same uniform in thickness. I marinate them overnight in a bit of canola oil, 2 parts soy sauce to 1 part red wine vinegar, adding garlic plus oregano & pepper.
This is the trick, I start my smoker on a higher heat and grill them to get the grill marks on all sides which seals them up good. Then put them at a low temp on smoke for just enough time(no more than 90 min total cook) to bring the center up to 145 to 150 degrees max. You can boil the leftover marinade and baste with it if you like. Because of this method, you might not get a smoke ring due to the shorter cook time, but you will like the smoke flavor mixed with that marinade!!!!
Steve