I would call SR and ask. My last few EU/US flights have been on DL equipment other then what the book said. I was expecting 767-300ER and wound up with 777 twice and MD11 3 times. So, you can not rely on the books, they are a guidline. DL's web site usually gives the correct equipment when I look at my seat assignments, but the 777 was listed as a 767-300ER. Again, call SR and ask, in fact call 10 times and take the answer you get most often as probably being correct.