So, I haven't fought with it since I completed the procedure yesterday, but I believe it'll work.
Rewind. Okay, I ordered the Madcatz SFIV Fightstick Standard Edition a few weeks before SFIV's release and got it towards the end of February. Lego and I had been feverishly competing in Street Fighter Alpha 3 on the MAME cabinet, and I reckoned it would be fitting to have two joysticks for the PS3 for the new release. Unfortunately the Tournament Edition stick had already sold out everywhere.
No real problems initially with the stick, though occasionally it would momentarily stick in a diagonal, but I figured it would loosen up with use. It actually got worse. I also had an issue with the R2 (third button of the second row) being intermittently non-responsive.
Did some searching online and learned I was not the only person out there with a joystick issue. For some reason, in the manufacturing process, Madcatz did not glue down a metal washer on the underside of the joystick. When loose, it will cause the joystick to stick in a direction, and prolonged rubbing while loose can actually damage the printed circuit board that transmits signals from the directional microswitches to the wiring terminal. I ignored the sticking for awhile, but it eventually stopped registering Left inputs and it was quickly time to take action.
I weighed the pros and cons of voiding the warranty and working on it myself, but faced with being down a stick for the foreseeable future, AND seeing the upside of failing the repair and replacing the joystick entirely (an enticing proposition) I popped it open and went to work. The only mishap was a sheared panhead screw that, as it turns out, didn't even need to be removed. Oh well.
First attempt to glue down the washer was unsuccessful, but a renewed effort using my traditional workspace was successful. The washer stayed put, and the joystick was no worse for wear. Reinstalled, and tested, to determine the stick was now fine, but the loose washer had damaged the PCB. A little testing and retracing with a mechanical pencil, and I was back in business. Also swapped R2 for L2 (which worked fine). I never use L2 (KKK) so I didn't really care how it reacted. These "light action" pushbuttons featured a bearing and spring mechanism; much more sophisticated than the run-of-the-mill alternatives we used on the Cabinet.
Everything (save the rubber feet) is back in order, and I plan to put it through some rigorous testing next I have some time at home to devote. Fingers crossed, yo.
Oh, and many thanks to this article for all the info and images.