Can the 8K knob be installed on a 9K chassis? March 02, 2016 17:00 Answer No, the two are not compatible. Applies To 9K, 8K Additional Information Related articles Lubricant for key combinator? 45H & 47H Mortise Locks How to Order: 45H Series Mortise Locks with Visual Indicator Commercial Hardware Mortise Cylinder Configurations for BEST 45 H and 45HW What is the Part Number for the 40H Trim Cassettes