I was able to get the instructions from Lax. basically in the IS configuration you need to create a profile for each GPU, then in ISBoxer select which character/client will use what GPU.
For example, I made two profiles and set it up so that my main would use profile 1 (GPU1) and all 4 of my slaves would use profile 2 (GPU2)
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Shu'Halo
Warrior - Warlock - Druid - Priest - Mage
Adamus - Azzeddar - Elistriel - Jazeela - Zimrinauth
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