Kohler K-76395 Installation Manual page 6

Mark the Pipes - Bowl Side (cont.)
Firmly insert the gasket end of the inlet pipe into the water inlet,
pushing until it contacts the bowl.
Position a level or other straight edge across the back of the bowl.
Mark the inlet pipe at the back edge of the bowl using the level
as a guide.
Remove the inlet and outlet pipes.
1247364-2-A 6 Kohler Co.