willysmjeeps.com

Is the fitting on the back of the crossover tube that the vent line to the carb attatches to threaded onto the tube and removable, or is it part of the tube?

I can see a threaded section from the inside of the tube, but want to be sure beforre I start trying to turn it.

If you rub the paint off around it, you may be able to tell if it is silver soldered on. If not then it is probably screwed in. However since the tubing wall isn't very thick I would say it is most probably soldered on.
I don't have an original tube to tell you either way though.
I made the tube I am using on my jeep and soldered the fittings on.

Mine is soldered on. But I cannot speak for them all.

The soldered in nipple on both of mine is threaded both internally and externally because it's a reducing nipple or bushing. It makes sense that Willys would just use an off the shelf threaded standard hardware reducing nipple and solder or braze it in place.

Thanks guys.