I ended up doing three 3" rib-eyes tonight though no pics, they were 2.5 hours longer than expected at a 4.5 hour cook 200F-210F with new (not recycled) briquettes.
These were regular beef, not AAA cut (little easier on the wallet). These ones were actually 3" thick so the last one must have been slightly less, more like 2.5".
Susan Z: I used your tip about searing over the chimney starter (full). Seared them on the top WSM rack placed on top of the chimney. As claimed it worked like a champ. I got a robust sear at around 40 seconds per side.
Smoke wood was one chunk of mesquite for only 45 minutes (no oak on hand). Seasoned with Montreal steak spice when foiled. This combination of smoke and spice worked very well, everyone thought the flavour was fantastic. Light but distinct mesquite flavour.
As per guest request for medium, one was removed at 153F then foiled and kept under a towel for 20 minutes. It ended up medium. At the same time the other two were transferred to the gasser for 4 minutes per side because the remaining guests wanted medium well or well. I was quite pleased that I nailed that target perfectly as well.
The steaks were sliced to 3/8" then served on a platter. Medium on one platter and medium well/well on another platter. Fresh peaches & cream corn, garlic toast, BPs with bacon bits chives and sour cream.
Appetizer served 90 minutes earlier was WSM smoked bacon wrapped scallops rolled in real maple syrup (just prior to serving), cooked over outside edge of WSM top grate where the steaks were. I removed these morsels from WSM, finished by frying till I was happy with the bacon, then rolled in syrup and individually tooth-picked. Some guests licked their plates, really!
Here's the rub. These were really good steaks, but nowhere near as tender as the previous steak which was an AAA Alberta steak (aged minimum of 14 days). I think it's safe to say the lack of aging had a great deal to do with the tenderness but I'm not sure how much the final cook temp had to do with it. The AAA was foiled at 143F, the medium tonight at 152F. Also, the cook time was 2.5 hours longer. Your thoughts?
Butter. Thinking next time I will coat the entire top surface with 1/4" of room temp butter instead of the square frozen chunk. For some reason, on the previous steak the butter pooled but not so on two of these guys. Just want a really good uniform butter coating to help retain moisture and maybe add some flavour.
Now I must go get some 1"-1.5" Alberta AAA rib-eyes and grill them to really tell if doing them on the WSM has some advantage or not. I'm pretty sure one advantage is that you can do a 3" steak by searing, applying indirect heat, rest then slice, platter and serve without worrying about burning. Secondly I think searing then indirect cooking might be the most delicate way to cook the beautiful aged AAA meat.
I'm gonna have to go on a diet after this