Dell 5100cn Color Laser Printer - Manual (Page 206)

4. Grip the knobs and gently lift the fuser out of the printer.
Installing the New Fuser
1. Unpack a new fuser, grip the fuser by the knobs, align it with the slots in the printer, and slowly push it in.
2. Completely push down the fuser by holding the knobs at both ends of the fuser until the levers next to both ends of
the fuser return to their original position.