I've done boneless beef "country style" ribs on the gasser before, Bruce, but not in the SI (shame on me, but so many meats to smoke, and so little time!). Beef country-style ribs commonly come from the chuck eye roll, which is also the source of the famous Delmonico steak, and chuck eye steaks (they're cut off of one end first).
Chuck, if cooked too quickly, can be tough (in my experience). If I were going to smoke these, I would start with a marinade or brine, rub of choice (or just a simple salt and pepper), then slow smoke them at 225 to around 140, then maybe a quick sear on the grill. These are thick enough to get a thermometer in, unlike pork ribs. Low and slow would be the way to go.
By the way, here's a pretty cool reference on meat (this page is on the ribs):
http://www.beefinnovationsgroup.com/Valuecuts/chuckroll/#/bonelessCountryStyleRibs