the solenoid needs to be rubber mounted in a place with ventilation. put is on the airbox side somwhere up front. and that way all you need to do is run hoses from the actuator and from the boost source to the solenoid. and put the plug from the ebc controller to the solenoid up to it.
if you are running the ebc controller itself youd want it to be in the cabin. so assuming you are going to run it in the glovebox. run a tee from a vacume line that runs from the inlet plenum. so u can get it as close as u can to where you want it, so the hose run stays as short as possible, before it actually needs to be tee'd.