I have a 28-30-120 single shot Stevens with 2 spare barrels, that was handed down to me from my father. From what I gathered on the internet, swapping barrels is pretty straight forward. Remove a set screw from the shank, and unscrew it. However, I'm puzzled about how to replace the ejector. I haven't tried removing it yet. I just want to get as much information as I can first.