Hey Ken,
I dont know that you need it, but i have a few tips if you want.
If you can get a party of all the same people, to get the supplies needed, and stick together, you can do all 3 in about 3 hours (faster if it is a static, and everyone knows what they are doing).
2 RNG and 2 SMN is really unccessay (although im sure it would work).
SMN only does "Alot" of DMG to them, if they use 2 hour. If your gonna do all 3 in one night, then you dont want everyone using 2 hour on the first fight. The ENM fights themselves are pretty darn easy, as long as everyone stays calm (and they all get into the fight !!).
Dont attack the BC untill your positive everyone is in. We lost a few members on my last Dem run, because the SMN didnt get in. For some reason the SMN took 3 times longer then everyone else accepting the mission ><.
You need a WHM (for tele and raise), and make sure at least your WHM has a reraise scroll. If things get hairy they need to use (again i dont know that you need this info, just giving you my experiences).
And last but not least, good luckk beating my last parties record on Mea :p