On pretty much any game with a ball trough, I remove the glass, reach in thru the coin door and manually flip the ball plunger up to eject the ball into the shooter lane. On my EMs, there's just one ball in the outlane hole that's easy to grab.
BTW, it's good to remember to remove the balls BEFORE lifting the playfield. Otherwise, balls can roll out and bounce down, potentially damaging something. (Yes, I admit this has happened to me a couple of times.)