I also own a C134 and just bought a Opus 150W last week. I should have it sometime next week. I was wondering how you are going to mount yours?
I am thinking about going out of the side behind the keyboard and PS/2 sockets by cutting a grove about 1.5" in length 0.75" in height or going out the back above the video where there are 9 small holes. I would enlarge the center hole (of the 9), disconnect the wires from the ATX plug, feed the through the enlarged hole and reconnect them. I am not sure how I am going to mount the PSU to the case, either on top or on the side. I will let you know how i make out.