Assuming you're modestly handy, it's a 10 minute job with the "new" OPV style. The required strength is less than that needed to open an average peanut butter jar.

Haha, i figured it out.. I turned it about one half turn ccw.. warming up now and we will see....

what do you guys think that the lowest pressure my silvia could be at now? I dont have a gauge handy but I have one coming in the mail..

Update,

I have been pulling shots after turning the opv 1/2 turn CCW with great success, however the flavor was not up to par. I got my portafilter with the gauge in the mail today, the 1/2 turn of the OPV took me down to a gauge reading of 8 bars when the portafilter is completely locked in. I turned the OPV slightly back clockwise and now I am getting a reading of right about 9 bars. Assuming that the gauge is fairly accurate, what brew pressure is this? I have head that the pressure is about .5 bars less than the reading on the gauge. Also, I dont know if it matters, but the portafilter I got with the gauge does not permit me to use a basket in it. I would appreciate the input...