First mix up your dry rub (Old Bay, paprika, garlic powder, oregano, and pepper).
Rub the top round with the pre-mixed dry rub. Let it sit in a container, uncovered or lightly covered, in the fridge for 2-3 days. This gives the rub a chance to absorb into the meat and start to break it down and tenderize a little bit.
After the meat has sat for a few days, fire up the charcoal grill. Get it nice and hot, then grill the meat for only about an hour. It can be longer if your meat is a larger piece. You want the internal temperature to be 120. This will have your meat rare on the inside. If you don’t want rare, cook it a little longer, but be aware that cooking it too long will make the meat tough.
Let the meat rest, or let it cool down completely, if you want. When you slice it, go against the grain and slice it as thin as possible.
After it’s sliced, reheat if you need to, serve on a bun, and enjoy!