I had a chance to go back to i3Detroit on weds night, and hopefully have the tank finished now! Still need to check for leaks (with water first - i've made that mistake before), and then re-seal the inside, but both fittings as well as a new return tube are welded on.
Return tube welded in & ground flat
Visible, but pointed towards the back of the tank where the pick-up is - much better than before
I thought this bit, welding a nice thick NPT bung onto the thin sheet steel with that much of a gap was going to be a big pain, but it actually went very smoothly
All done with that one! Right around the seam and cross-over tube was a little tricky to get the torch into, but it got done
And the other bung for the return, over the hole where the tube was welded into. I didn't remove the paint in a large enough space around this one, and it caught fire when I was welding. Took me a little bit by surprise, at which point I burned a hole in the tank which had to be filled, explaining that blob to the lower left of the bung.
So, the only welding that I can think of left is for the O2 sensor bungs in the exhaust, and possibly for a fuel pump/filter bracket