Start probing for tenderness at about 190*F internal or so. It should have no resistance in several areas with a skewer, fork, probe, etc. If you get resistance ck back in 30 minutes. If no resistance - it's done. Sometimes it's 190*F sometimes it's 205*F or anywhere in between. As a kind of joke I always tell SWMBO it's done at 203*F. I cook at 250*F +/- 25*F pit temp.