These two posts got it done!
SKB shows a lug that fits into the top bolt. In the video, he shows depressing the lug to remove the top bolt.
I used a punch to push down on the screw boss and it moved down like the lug in these two examples.

This was enough information to be confident that the top bolt would move rearward given enough motivation.

Originally Posted by SKB
[Linked Image from i.imgur.com]

This is mine, you slide the top bolt out to the rear, under it is the top tang pin. The top lever screws into a yoke that engages with the double under bite bolt.

Originally Posted by KDGJ
At about 3:30 into this video, Ian Sweetman shows how to take apart a WR boxlock with the WR C-bolt top lever.

WR boxlock

Ken

Mike