Briggs did not make the snorkel, so it isn't covered in their manuals. You remove it in the same way as a normal Briggs air cleaner: just undo the central vertical screw, and you can lift off the little air box under it. Remember though, you must put that screw back in to run the engine. You don't need the air cleaner, but you do need that screw, or it will become very rich - perhaps too rich to even run.
You then have to remove the air cowl, then the vertical pull starter, before you can take the tank and carburetor off as a single unit.
