Mechanic suggested that I replace the engine mounts. Found this one right next to the coolant overflow.

However, there is this one listed on the parts schematic, and for the life of me, I cannot find it.

 

I think by now based on the date of your post you have found the location of the mounts.
But for newbies finding this post, there is one mount by the Antifreeze expansion tank, one by the back of the motor on top of the rack and pinion, one almost below the air filter, another on in front of the engine below the radiator.