A printing press for printing on metal cans includes a plurality of inkers. Each inker prints a different color ink on the cans, and includes a first module, a second module, a roller and a support member. The first module has motors to drive output shafts. The second module has ink displacement units, an ink inlet to provide ink to the ink displacement units, ink channels to transfer ink from the ink displacement units to ink outlets of the second module and input shafts to removably couple to the output shafts of the first module. The roller receives ink from the ink displacement units and transfers the ink toward the cans. The support member supports the first and second modules in at least one position relative to the roller. The support member facilitates removal of the second module by a press operator for cleaning the ink channels.