Abstract: A clutch conversion kit is usable to convert a truck or other machine from a lever actuated dry clutch to a fluid actuated clutch. The kit (49) includes a hub (50) which engages an input shaft (56) of the transmission (16). A fluid pressure actuated cylinder (68) is mountable on the hub and is operative to selectively axially compress friction discs (122) and separator discs (124) included in a disc pack (120). A flexible drive coupling (170) and drive ring adapter (146) are engageable with a drive ring (138) that is engageable with the friction discs. A pin (204) is positionable to hold the cylinder in a fixed rotational position while a shaft collar (202) and other components of the kit are used to assure proper positioning and operation of the components of the kit.