I installed a 332c in my 06 Classic. I believe a 332c and a 522c are the same size. Use the pattern from the new install kit to make a cardboard jig. Remove your steering wheel. Place the jig where you want your new unit to be. Outline it with a fine tip sharpie. Use a RotoZip tool with a tile cutting bit to make your cut. Be careful and go slow! It will work like a charm.
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