You provide power for the gimbal from the solo and wire into the either the Mavlink signal or the PWM signal on the Storm32 controller use the controller Paddle signal...
see this thread for specifics.. Gimbal wire diagram for aftermarket gimbal
thanks think I'll order two, just checked ebay about $68 not bad for 3 axis. Appreciate the help and link. I have three Solo's one with gimbal and two without. I need to get gimbals on the two without.