Does anyone see a problem if I substituted an equal amount of kosher salt (Morton's) for the sea salt in the brine? Thank you!

Thank you all. Dynamo, I wasn't particularly asking about Morton's, but really Kosher salt vs sea salt for this brine in general. FYI I did make the brine, substituting the kosher salt for the sea salt since neither Amanda nor LBF seemed to think there was a big difference in a brine. I used Amanda's suggestion to reduce the salt since I had Morton's. It was perfect! (I halved the recipe and used regular honey, then brined a cornish hen, which I spatchcocked and roasted at 450 for 30 minutes along with some root vegs. As promised, the hen came out juicy, flavorful and with a beautiful mahogany skin. I also followed wssmom's brilliant suggestion to use less water in the brine, then cool with ice cubes, so that I could brine right away.

I don't usually use Mortons salt because it contains iodine. That said, I have never tried their "sea salt" . I suppose it would work if there are no additives.

tarragon, maybe the recipe chef would have a diff opinion, for the purpose of just a brine, i can't imagine that sea salt would make that big a difference; and it certainly is very cher compared to kosher salt.
BTW, many recipe chefs rarely see the hotline or check the comments on their recipe pages. So when i have a question that i really need ansswered, i click on the chef's recipe and then from there i click on their name; and then on their member page, i send them an email by clicking on the envelope symbol. those emails go to them directly.

Perfect answer, thank you!

It should be fine but I'd start by cutting back the salt by 1/2 cup and taste the brine. The reason I say this is that Morton's kosher salt is known to taste "saltier" than other kosher salts, so you may find that you'll want to scale back the salt a little.