Direct replacement - sorta - filler neck - thankfully, the PO or somebody down the line when they went over to the poly tank they cut the metal line off the old tank and then used fuel line to bridge the gaps to the fill neck.
I included a pic that indicates what I am talking about...I just loosened the hose clamp and moved the whole assembly over to the new tank kit.
It never leaked when I put gas in it - and when I put a few gals in it today there were no leaks again - so I would consider it good to go (minus those damn bolts).
Now I will just need to get a replacement sending unit for the old one and it should be good to go again for another project.
Did I ever mention that dropping these tanks is a PITA.