Got a tech tip for Voyager 12's from your personal experiences, or one complete with pictures and instructions, here's where to post it. You can also ask about tips or procedures here.
Yes, paulezy,I accidentally (lost) a sealing ring the same way during one of my oil changes. I keep some spares now, in case I dump my oil (with ring) in our shop oil furnace reservoir,and it is lost forever.
Yes we are all human and we do get things wrong from time to time. That is why us old dogs hang around to give whatever aid and comfort to those who need it.