Wow, that was fast.
It is the left side latch.
I either have to stick my finger straight in through the ejection port with the shotgun oriented 'up'; or I have to roll it to the left a bit to go in from the bottom.
I really don't want to send it back.
I'm a member of a range that has a shotgun course and there's someone there that might know what to do. I'm sure it's not the first one to do it.
Is there a special tool to r&r the latch? Don't know.
I'll visit the range and ask around to see if there's a Rem 870 mechanic on board.
Thanks.