Kansas uses Pearson Vue, which is based in Philadelphia, PA, to do their testing. You can take the test at different locations in the Kansas City area, where the tests are given Monday through Saturday. They also have several locations throughout Kansas, including Wichita and Topeka, and in those locations, the test is typically offered two to three weekdays and every Saturday.
Missouri uses PSI (formerly AMP) for testing. PSI is located in Olathe, Kansas. These tests are given in Kansas City every day of the week and the third Saturday of each month. In St. Louis, the test is offered every day of the week and the second Saturday of the month, excluding the Monday following the second Saturday.