I still think you may have extra gaskets in the pic you showed.
Take an original spigot, make sure it is not bent where the screws go thru (crucial).
Now with the new gasket out, but old used still in, your spigot should slide in and be touching the shoulder where the screw fastens it to head. IF there is an 1/8 or more gap, you have an extra gasket or more in there.