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Personally I would not change anything. It should work just fine the way it is, but with the steaks you already have. As for how long under the broiler, I would go by temp, not time. It all depends on how you like them cooked, how thick they are, how close to the broiler, etc. Use a thermometer and you can't go wrong. Just remember to let the steaks rest for a few minutes after cooking before you cut into them.