Kohler K–15708 Guia De Instalacion página 5

Prepare the Site (cont.)
The diameter of the valve holes should be 1-1/2" (3.8 cm)
maximum.
When using the K-T15880 or K-T15881 spouts, provide a screw
hole to prevent spout twist. The center of the screw hole should
be 3/4" (2 cm) from the spout hole center.
Kohler Co. 5 114183-2-CB