Broken Analog Stick related to cracked faceplate?

I turned on my PSP this evening, and much to my dismay the analog stick was messed up, automatically moving right (returning a right value, not physically). I checked online and started looking at guides for analog stick replacement, and opened up the faceplate on my PSP. At this point, I realized that a small fragment of plastic that holds the faceplate screw in directly next to the analog stick had broken away, so that the screw was no longer holding the faceplate at that point. I wrote a little Lua app real quick to show the analog X and Y values on screen while I messed with it, and I noticed that applying pressure on the faceplate messed with the values the analog stick was returning.

My question is: Is it the faceplate or the analog stick? My assumption is the faceplate, but I'd really prefer not to drop $20 on a new faceplate if it's just the analog stick. Is the pressure of the faceplate screw at that point a major factor in a working analog stick's operation?

Thanks ahead of time, any help is appreciated.

I had a problem similar to this one with my GC controller. The internal analog stick had something broken in it so I had to stuff it with tissue paper.

So, maybe if you post some images we can help you out since we don't really see what's happening ;).