I just finished this over the weekend. I'm a merc with full heal spec geared out ok for not doing any war zones. I had tons of problems with this. I want these guards heals!
Ok now for how I did it. The first night I had tons of problems died way too many times and was just about to break everything on and in my computer when I fleet passed out of the whole thing and shut down. I tried every companion I had nothing worked.
The next day I crunched a few numbers and looked over Mako's gear. She was a bit under geared for that so, instead of throwing tons of creds away to repair bills I took a trip to the market and fixed her gear.
I went back to the ship; got back to the insane insta heal super guards and fought for my life. The best advise has already been given. Use your interupts wisely, do not go into this fight thinking it will be like most of the others. Be smart and grind them down; it takes a bit of cool headed judgement but, it can be done.
And I want to pat myself on the back, I did not use a buddy's help and I sure didn't use any bugs or glitches to bring them down.