New guy, What tranny should go behind a 360?

Hey guys, I'm a little ignorant on the older cars so please bear with me. I'm going to put a 360 crate motor into my 68 dart. I've always heard of the 727 transmission, but I see a lot of 904 trannys on this forum. Which would you guys recommend. I'm a long way off from needing this info, but just trying to be smart and do my research. Thanks guys.

Kenny

P.S. I need an automatic, not manual. Not sure if that makes a difference.