Converting a GST 7.7 to brushless. Help?

[tashpop]

well i get to make this journey with you. i was really wanting to find a gsr, but i haven't found any rollers come up on ebay so i scored at gst roller yesturday. i really don't know which route i'm going to go for esc's i have right now are a hobbywing 12s 100a or a mgm22418. decisions decisions? i can't wait for this thing to arrive, i've never seen one of these trucks in person.