well i think if i had two i would put them in together because they are used to sleeping together- so one less thing to deal with (crying because they are lonely) however, you stil want the space to be small so that they can't pee in one area and sleep in the other. you want them to wake you in the night when they need to go out and they will do this if there is no room in the crate to pee so make sure they are close enough to you at night so that you can hear those little cries
Welcome to YT- congrats on your TWO new babies!