[Where on Hoth do I get the mission to get HK-51]

They didn't put it in the game yet? Pitty.

[Where on Hoth do I get the mission to get HK-51]

I know it's somewhere in the Glacial Fissure (sp?), but I've been all around that part and have yet to find the droid that points me to Bren. I really want the assassin droid on my team, but I can't find the starting point. Please help.