First off you are going to loose at least 30% of it's weight when you barbecue it, and there will also be some fat trimming involved as well.
Since it's for chili, and it will make some dang fine chili meat by the way, I'd eliminate the barbecue and just trim it and do a coarse grind (or hand dice) on it. Then break out the dutch oven and get down to business. You could always put the assembled chili on your smoker to pick up some wood flavor.
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