To allow the electrical connection through the cup, two holes need to be drilled.
Just drill the holes according to the drawing.
The cup is part of the filter housing, which uses as a base to the whole cell.
Make sure you buy clear filter housing to see what happening inside when the cell
When working with the drill make sure you take the required safety measurements like
goggles, gloves and some kind of holding device to hold up the cup in place while
drilling - this way your work will be more safe and more accurate.