My favorite way to do it is as follows:
Lightly cover the roast in sea salt
Wrap in cheese cloth, let set in the fridge at least 3 days, 5 - 7 is better
Remove from fridge wash off salt and let sit on the counter for 6 - 8 hours
Season with Johnnys, make small cut and stuff whole crushed garlic cloves in the meat
Place in oven at 450 for 20 mins, turned down to 325 and cook to an internal temp of 125
Remove from oven wrap in foil let sit until internal temp reaches 135.
I like it this way because not everyone like medium rare. The ends will be more medium and the center will be closer to medium rare cooked this way. If you want it medium rare throughout drop the temp to 200 after the first 20 mins. Everything else stays the same.