I would prefer to control the entire water meth system with link ecu itself. Bypassing the aquamist control box. Our ecu is more than capable of controlling water meth. Select an unused output, configure it as GP output, use condition 1 AND 2 (MAP and RPM) and you get to select whichever rpm/map you want the meth to start spraying. Use an external 30A relay to run the water meth pump controlled with the ecu output. You can then use 4D ignition and fuel to trim fueling and timing when water meth is running.