X5 stalled/set codes while being inspected!

[workingonit]

I received the Hella pump today, a day earlier than I expected. couldn't wait topull out the OEM, and install the new pump. That was 2 hours or more ago. I still haven't got the locking ring back on.

I even got the wife to come help me, because of my bad left wrist & thumb, and my entire right arm is getting worse by the day (I know, excuses, excuses), and we finally gave up. Dhe went back to her new living room make-over project, and I'm in my office looking at videos to see what I'm missing, or doing wrong.

I'm making sure that the tab on the upper edge of the pump assembly is going into the slot of the serrated ring, but whenever I'm trying to hold down the pump (it's strongly trying to pop-up), and simultaneously trying to get the locking ring to catch threads, it cocks sideways and I lose my grip.

What am I doing wrong? I've never ever had a problem installing an in-tank pump before, but it's happened now.