I've been working on making some minor repairs on the QRX-7500 I bought from someone on e-Bay, and I've run into a snag on one of the malfunctioning components: I'm in the process of replacing the "Level Set" control potentiometer just to the right side of the VU meters. To get this control unsoldered, I would think I need to remove the PC Board that controls the balance controls; it's mounted slightly to the left of center, and flush against the bottom inside of the inner front panel (I say that because the outer control panel has to be removed to get at the knob shaft nuts). The knob shafts for some of those balance controls are what secures that board to the inside of the chassis; they use a small hex nut on two of the shafts, and then on the Rear Balance control, they use a big Brass colored threaded spacer. I can not remove the spacer from that control, and therefore, I can't remove that PC Board that's in the way of me working on the Level Set control. When I turn the big spacer counter-clockwise, the outer sleeve of the Rear Balance control is slipping on the front of the potentiometer body. Would anyone know if there is another way to space the inner front panel chassis front away from the rest of the chassis so maintenance can be performed? If I don't get any suggestions, I my have to (very carefully) cut the big brass spacer off of the front of the Rear Balance control potentiometer. Please let me know if you have any suggestions. Thanks!