Correct - passenger side has the weld nuts, drivers side has the grommets.
If the fuel line is gone/missing, let's hope the clips are there. If they are not, then we'll check the date on the rear - assuming its the original then the 3.55 ratio is a pretty good indicator that it was the L78 vs. the L34.
I know you said it was a bench seat car, but look for a heater box like this one - I was surprised with this in my BB car, not realizing that it was unique to console cars.
Once you get it home, you'll want to start scrubbing the firewall for codes like these:
Most Novas will have a large letter written in white grease pencil on the f/wall under the black paint that corresponds to the letter on the bottom row of the TT. It indicates the interior paint color. Also, the paint code is usually under the black paint too. In this pic is an 'A' for black interior paint ('B' is blue, 'G' is green, 'S' is sandalwood), and '79' is my paint color - rally green.