Fuel pump test connector TIPS
With the leak you describe I would not fire up the engine until I find out the source of the leak......You could burn it up......
Above Marc describes the way to hot wire the fuel pumps without turning on the ignition key using electrical test leads directly from the battery to the Fuel Pump Test Connector.
........I would do that to get fuel pressure which you apparently have but your reason is to find the fuel leak
without getting anything electrically hot in the engine compartment except the fuel pumps........That is my thinking at the moment......
First...... air out the engine compartment........ then only hot wire the fuel pumps for a couple seconds at a time as you should smell the gas fumes quickly at the source of the leak as you describe the leak is a BIG leak
Do not take anything apart until the leak is identified
This is a gas leak, not a vacuum leak which a gas leak should be easy to source.....
There is a drain line under the starter and if the leak is large and under the plenum you should see gas dripping under the bell housing.