Hi Jeff,
The interference is circled in red.
IMG_5533_zoom.jpg
As the nose goes down, the tube contacts the fitting because the weld bulges out a bit.
IMG_5529_note.jpg
Yeah, I didn't want to grind weld and weaken the joint, but I'm worried about putting a weak spot on the fitting as well.
I decided to email John McB directly as well to get an official opinion, since it looks like this hasn't been addressed before.