On the underside of the tank, there are the wires for the fuel guage. A small square black plactic cover attaches to it, I guess as some sort of dust cover. It has a place to attach a hose to it. Where would a hose lead from there and for what purpose?
Is it for the hose that goes from carb to the right side air filter? Is this just another place to attach the hose to?

Thanks!

When I replaced the tank on my 95 vn750, nothing hooks up to the plastic part. If anything did, it would just be left open and dangle like the original battery vent hose use to (you replaced the battery with a maintence free one didn't you?) so if the gasket or sending unit leaked, any gas would be diverted. It would NOT hook up to the carb or any other place