I would guess you have a leak in one of the sender unit lines, very typical for these cars.
I just had mine changed a couple of weeks ago, I also replaced the tank while there.
A jobber sender unit cost me $130 Cdn and the tank was $140 Cdn. Be carefull with aftermarket tanks, I saw 3 different tanks that had a slightly misaligned ring in the tank for the sender/pump assembly. In my case the gauge would get stuck at 3/8 tank. They had to remove the tank and trim the tabs on the sender unit to get the alignment correct.
Within the space of a few weeks, I went from smelling fumes to noticing a leak, to seeing a stream of fuel leaking all over my exhaust
Hope that helps...