3-2-1 is usually way too long on any of my cookers. My benchmark on the WSM is 2-1-1 for untrimmed spares, which is what I usually do. On St. Louis ribs, I usually go 2-1-0.5 and check for doneness. I did a couple of racks of loin backs on the WSM without foil last time and they were not as tender as usual IMHO although everyone else raved. I'm usually cooking about 275 on the WSM with the IQUE and 250 on the offset. I rotate positions on the offset hourly, especially if I'm not foiling.
BBQ Apprentice - Old Country Brazos offset, 22.5 WSM, Various gassers, portable grills, etc.