I agree with the feeding in their beds suggestion. My puppy b itch started by peeing etc. in her crate overnight. I told my vet and she said feed her in there and it will stop - it did. I'm not sure whether this will work with males doing this because this is marking whereas my puppy was just 'going'. Happily although I've kept entire males, and stud males at that, none of mine ever did this. Yes, castration might help, but it doesn't always work. You might consider castrating one of these boys (are they litter brothers, because if so, there may be a dominance thing going on, even if they don't actually fight). If you do this, pick the more submissive of the two because if the dominant one doesn't get a reaction, he may stop peeing.
Another suggestion - if this happens overnight, get them separate crates and have them in your room with you. If they are with you, they may not stir during the night, and if they don't stir during the night, they won't pee!!
Hope one of these ideas works.