Okay so I'm just now watching the video you linked and that might be the missing key... Not looking forward to undoing all those bolts but I'm going to give that another look.
Absolutely shocked that this might be the way to get them separated and that I didn't notice a different way to get that second piece of housing apart.
That said, I'm still not sure I understand how that housing comes off but I'm going to give it a shot in the next day or so.
Crazy to think that every automatic I've worked on uses 3 or 4 bolts for the torque converter and these things used a whole hardware store's worth...
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