One obvious issue with using the audio fader is that there are two separate pots built into it: one from center down and one from center up. Since the center position is 0 ohms, that would have no effect on the blower speed and would therefore be the "high" setting of the knob. You would then turn the knob down to achieve slower blower speeds. Turning the knob up (or forwards) would be useless and confusing. To prevent this you'd have to physically stop the knob from going past center - probably with a small screw or something. There are already two built-in stops on the plastic wheel; inserting a screw through the knob with a little nylon spacer would effectively act as stop. It would just have to be placed carefully. Along these lines, another thing to consider is that the max ohms seem to be 55k (even though it's printed with 20k), which is more that what you recommend Jeremy, and if there is a problem operating the blower with too small a current, you could install another bumper at the other end of the knob to prevent it from going past 20k-25k.