Hi there
Yes, the line is horizontal and the gasket is in place.
Re the needle, when I take the plate off and hold it as it would be on the machine, the needle doesn't drop down out of the tube as easily as I would expect. But I guess the gravity pressure of the fuel is enough. Having looked at it again, I don't see where a spring would fit so I don't think it has one.
I haven't dismantled the other bits you mention.
The brass fixing screw in the middle of the end plate that also serves as the main jet - does that need any particular treatment?
