Siteunseen,
Thanks for bringing that up. On my filler hose, the #18 line you refer to has been shut off by someone at some time. The plastic fitting #14 appears to have been heated to the point of melting, then crimped shut. As between you and Dennis, this is becoming more interesting / confusing. If the reservoir is meant to catch fill-up overflow via Line 18, then I should make very sure the tank is sound. Or, if we ditch Line 18, as appears to have been done on my car, one would have to be very careful on refueling.
Another thought with respect to the reservoir - if I patch-repair it as has been suggested, would the application of a fuel-tank slush compound (as I have already done on the fuel tank), ensure a good seal?
And yes, I should track down the "young fella who lives just south" (about 1.5 hour drive). This is my first 240Z project, and it sounds like he has vast experience.
This proving to be an interesting conversation.