Oh, might as well list what I used to scrape by, as something for others to compare against:

Name-------HP---Atk
Andromeda:-7108/42493
Atalanta:---5494/39593
Triton: -----5769/38774
Nike:-------5504/36974
Snow Raph: 6414/40474

Ea:---------6404/43095
Enkidu: ----5392/39687 (1st attempt)
Cupid: -----5829/37274 (2nd attempt)

Assault: 109% (146 skill lvls + 36 directly from assault M/L) + 2 pride (L)
Defender: 20% (well, HP's already listed above)

Jack Frost (main!)/Yamata no Orochi/Yggdrasil/Jormungandr/Sphinx/Tiamat
Friend slot is whatever Rudra I can find from random non-friends

I did (barely) succeed on both attempts so far. 1st attempt had Andromeda die off to the raging overdrive, so I picked up the 3+ SRs and 3+ Attack types (Atalanta/Ea/Enkidu)
2nd attempt had Andromeda survive (thus the soul survives point) and res allowed me to insure the 5+ members survive point.
I definitely don't hit hard enough for a Full Burst to take care of raging. Also, when it comes to cleanly pushing into raging to allow setting up for the trigger, I have very little room to work with. I probably should take advantage of the 2 turn duration on Snow Raph's damage cut...

Oh, and I actually full burst through the 2nd stage. I have enough healing and Snow Raph's damage cut to allow me to turtle to FB again in stage 3.