Set it out on the counter for 3-4 hrs to start,and that will help.
Your definition of med rare might vary,but if the roast had been held at 140* for a long time,I suspect you wouldn't get more than a couple degrees of rise.
I'd probably pull about 130*.
As you can see,this is why Smokin'Okie is so adamant about keeping detailed notes on your cooks.
This is especially true for cooks that you don't repeat often.
Shape,quality[select,choice,CAB,prime]will all affect your times.