[How do i get jet bodies off shell?]

Thanks.  Turns out I was off.  No threads OR silicone.  The jet body was just a tight fit into the rubber gasket set in the spa wall.  Some pushing, a bit of a turn, and it slowly came out.

[How do i get jet bodies off shell?]

I'm baffled at how this jet body is held in place.  I don't see a nut.  Is it pure silicone sealant?  Should I just pry/twist it off?  You can see it has a broken nipple - I've got a replacement for the jet body.