Have Carby out, keep the SMNs refreshed, also be sure that you engage the Carbuncles from different ankles so it won't get both in the ink attack.
The trick to this is really, let 1 SMN go in, do meteorite to let that Carbuncle get hate, and when that one is almost dead, let the other SMN do meteroite with his Carbuncle to make it take hate.
You switch hate back and forth between the carbuncles while you resummon them to make their HP full again.
No 2hrs needed, takes about 10-11 minutes to do this, no real time preassure, the RDM can gravity kite easily if things screw up a bit.
Have SS up at all times as he starts spamming TP attacks @ and under 25 %.
Everyone buffs up inside, stoneskin, blink, ext...BLM's run up cast Burst then have one run counterclock wise and the other clockwise, while the rdm is casting Refresh, Bind, and Grav. cast BlizzagaII untill both mages are below 200mp, then rdm sleeps and blms rest up then repeat running around and casting BlizzagaII
So far with this strategy I have one everyone with only coming close to death once.
Be sure to keep SS up at all times or you will fail. GL to all :D
RDM with any DD melee makes this easy. First time doing it for me and I did it twice in a row. Always keep grav'd, bind/sleep if needed. First time was close, second time was easy (slept it halfway to refill MP).