Rectangular Aspirator, 25 Litre

Q = How do I remove the plastic bung near the base, so that I can screw the tap in?
A = The bung should be unscrewed from the hole, using a very large screwdriver, or wedging  a pair of pliers or similar into the bung, and turning it anti-clockwise to loosen it. It can then be unscrewed by hand, before screwing the tap into place.