I have a terrible knocking sound coming from driver and passenger side, mostly driver though. I am pretty sure now that it is the mounts, i've been told before that they were worn. How hard are they to replace?

 

In my personal scale I would consider them easy.

The bottom 2 are mounted to a removable metal piece. This is the same piece where you jack up the car in the front.

The top pax side is the same one you remove when changing the timing belt. It is an improved design though so you must also replace the large aluminum piece that bolts to the engine. It will not fit the old piece without alot of grinding.

The driver's side you get to under the intake filter box and battery box. Just a matter of removing those pieces and the mount is right there.