Simmer in WSM?

How would I go about maintaining a simmer in the WSM? I was thinking about braising a chuck roast in the wsm to make po boys. I have made them on the stove and they come out great but I wanted to try it in the wsm. Would 250 do the trick? My plan was to bring the roast to a boil on the stove and then transfer it directly to the wsm, pot an all. Just wondering if this would be a waste or would it impart any smoke flavor.

Smoke the meat first for a while on the grate. Then put it in the pot with your other ingredients for the braise. Put the pot in the oven or back in the cooker (I do the latter). Cover till simmering well then keep covered or partially covered till done. 250 is fine.

Thanks for the input Kevin. So should I take the meat to 140 interal temp and then put it in the pot or is that too high? Maybe put the pot on the lower rack under the beef to catch the drippings and then throw the beef in the pot after it has smoked for a while. As you can tell I am always trying to add another dimension to the food I cook. Sometimes it backfires on me so I really appreciate all of your advice.

It doesn't matter what the internal is. I smoke 2.25-2.5 hours. I never bother temping as it's fairly pointless.

Here is a common approach for me. Since I found a suitable Lodge CI pot for the cooker I no longer foil as I did in the post; the pot replaces the foil.

No need to catch drippings. Chuck roasts of some size have plenty of drippings that will be caught once the meat is in the pot and, if adding liquid to the pot (I only use a little, as noted) and/or adding onions (I use a lot) or other items that contain a lot of water, there will be enough for braising.