@ Sauzo- Thanks for the tips.
I have a few weaned rats left and the small rats that I have aren't much larger. I'll be sure to feed him the smaller prey first. I'll probably have to order more feeders sooner than I'd planned, which isn't too big of a deal, even though the rest of my critters have food for the next 3-5 months. Do any of you feed your boas mice or chicks? I like offering a varied diet and all my other snakes eat whatever I give them. I've heard boas aren't very picky when it comes to food.