Stylus Pro 4880 Field Repair Guide 1/17/08
Pump and Cap Installation Printer Component, Software Item, LCD Display, Printer Button  Page 93.
9. Install the Trigger Shaft.
Insert Trigger Shaft into the 
Right Side Frame
Flex the Trigger Shaft from the back side of the 
Printer, until the end of the Shaft can be inserted 
into the Socket
Insert Into 
Socket here