It's pretty easy to do it the traditional way. Just get a tank, two melee damage dealers, a healer, and two kiters.
Our setup was NIN, MNK, RNG, BLM, SMN, RDM. The NIN tanked, of course, while again, of course, the MNK and RNG damaged in combat. I was the BLM, and I chose to be the healer of the group, which was very easy. The SMN kited one mammet around with Carbuncle, while the RDM kited another with usual RDM kiting tactics. After the first mammet was dead, we moved on to the RDM's. After that was killed, we pulled the final one, which the SMN had been kiting. That one was probably the easiest, because we had Astral Flow available, and the RDM healing the NIN, which allowed me to unload on the elemental spells.
All in all, just stay organized, and help eachother out. We had plenty of yellow liquid to keep the mammet being fought in DRG form, being that it was the least threatening. If it makes you feel any better, even with me as the healer(BLM), not one of us ever came close to dying. We had a little trouble with the first mammet, because it was in BLM mode for a while, but not even that hurt the NIN very badly.
Keep cool, and you'll do great! Best of luck.