I do big cuts of beef like that fairly often for work. I generally trim off most but not all of the visible fat first. Apply a generous rub at least the night before, but up to 48 hours is fine.
Set the oven to 300. Put a bottle of wine or the equivalent of stock into a roasting pan, then the meat and any juices that accumulated in the pan you kept it in. I would put this in the oven at 6am....and it would be ready for service by 10:30-11am. Let it stand about 20 minutes before you carve it. My oven is convection, by the way.