[MyFlat6]

It is an easy job. Word of caution: be very careful removing the fasteners attaching the valve cover, if you do not have a firm seating with the tool you are using, they will strip easily. I was able to replace mine without removing the muffler or exchanger but it required the right size Allen/hex fitting. If you cannot get a firm grip on all the fasteners with the muffler on, then you are better off removing the muffler to avoid stripping the bolts. I would order new hardware and the gasket to replace them. The torque for the fasteners is 10nm and you should use a cross pattern when torquing them down.