I have already done it on a different account back in Wrath and now I am re-doing it on this account starting from scratch.
Basically I am looking for people with 2 specific attributes:
1- Good at raiding
2- Commitment to gear up.
As the fight is no longer on a 1 hour/week timer, the achievement itself will be much easier to get.
The hardest(longest) part will be to grind the required gear.
The fight itself is a raid fight, so that is why we need people that understand the class they want to use and who can pull out good DPS and Healing. If you are not a raider, forget about this.
As for the gear, you will need to get a new character up to lvl 80 and lock the experience gain at that point, then farm a specific set of gear. If you are willing to put a month into that, assuming you are starting from scratch, then I will give you the instruction on how to quickly gear yourself for the encounter.
Message me either in-game or here. My in-game name is : patsolid