How thick is it, rick? Much thicker than a top round roast? You might
have to just adjust the cooking time accordingly (or I guess that's what you're asking, right?).
Here's my favorite recipe for LB:
1/2 cup red wine
1/4 cup soy sauce
1 tsp Worcestershire sauce
1 Tbspgarlic, minced
1/2 sweet onions, chopped
2 lbs round roast
Mix ingredients and marinade the meat for at least a few hours in the refrigerator. After taking it out of the refrigerator, let the meat sit out for an hour before broiling in the oven.
Preheat broiler and cook for 4-5 minutes (maybe 2-3 for your thinner cut). Flip and broil for 2-3 more minutes.
Remove and let sit for at least 20 minutes. Slice against the grain at a very sharp angle which will result in very thin slices.