Lexmark XC9465
Turn off the printer.
Open door A.
Unlock the fuser.
Remove the used fuser.
Unpack the new fuser.
Insert the new fuser until it clicks into place, and then lock it.
Close door A.
Turn on the printer.
Learn how to remove the fuser when you are installing a new one.
Replace the used paper bail to hold printed paper in place in the output bin.