Yes, you need to inspect closely. I just picked up a replacement tank and it had a little rust on it, so I treated it.

The INNER small tube is the fuel return.
The outer small tube is the vent....which interesting enough "stops" about 18 - 20 inches FORWARD of where you see the 2 hoses. Look for a steel tube hanging down with a rubber bell shaped thing on the end.

Here's a link to my fuel tank work:
http://www.peachparts.com/shopforum/3130873-post73.html

Here's are 3 pics of the bottom of the fuel tank I'm installing documenting the repair:







Good Luck and let's hope you don't have a rusted thru fuel tank.

__________________
daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more