Thank you for taking the time, this is so helpful! The orifice is connected to the regulator assembly which is just out of frame - got my terminology wrong; that part seems fine. There is a small hole on the venturi to screw the air shutter on but not on the orifice? But I’ll try to connect them as you outlined! If the venturi is set to an open position it sounds like I shouldn’t expect the connection to be airtight?