On my 4830 I put a valve and air chuck on the end of one of the inline filters. Then ran an airline from the air tank. It's not fancy but only cost $20. To operate, the sprayer engine has to be shutoff, but key on. shut tank valve off, turn pump switch on to make the gs3 think it's spraying, then hit the spray button on handle and cycle through each boom section. Have been doing this since my original 4700. Could automate it a bit with a solenoid, but would still have to get out to shut the tank valve. Could be done to pretty much any sprayer that has an onboard air system, or just use the air from the tender truck.