70 GS fuel lines, only one?

Car had no gas tank when I bought it. I have only owned 71s and 72s that had 2 lines on the sending unit and maybe even a return or vent on the passenger side.... so I removed the body from the frame today on the 70 GS 350 and only see one fuel line, nothing on the passenger side either.

I ordered the GM34B tank which I see was recommended by members.

Is that correct and would I use a sending unit with just one line?

Would I need to use a vented or non vented gas gap?

I have this fuel vent for the passenger side of the tank.

Thoughts? Thanks

 

Silly question, why did a/c cars have a fuel return?

 

Thanks Larry. So if the car was a 350 but going to have a 455, looks like I would use a 2 line sending unit, with 1/4 inch return line. I assume the 1/4 return line is then attached to an outlet on the fuel pump.

I assume I still use the 2 line vent on the passenger side of the fuel tank.