I like "Aircraft Stripper" from AutoZone.....available in pints, gallons and aerosol cans for the smaller jobs. It's not what I would call Eco-friendly but it will raise the layers of paint so you can hose them off with water.
A word of caution....make sure you're outside in a well vented area, no place close to anything you don't want to get splattered with stripper and I wear rubber gloves and a respirator when applying it with a brush.
It may/may not take a couple applications but it gets the job done and rinses off clean with with water.
Dave
