Hey Susan, to swap your surge brakes to electric over hydraulic, you're going to need to change out your actuator and add a proper brake controller.
For an actuator I'd recommend going with the Hydrastar Electric Over Hydraulic Actuator for Drum Brakes # HBA-10 if you have drums, or # HBA16 for discs.
From here, you'll need a brake controller. I recommend checking out the Tekonsha Prodigy P3 Trailer Brake Controller # 90195. This brake controller will work great with electric brakes,... view full answer...