That's right ,the Dremmel,but use a thin disk to cut down to the hole thus forming the slot and then very carefully grind away at the inside of the slot till it just allows a needllebar to slide through. A good way to start the cut first is to use a thin flat needle file on edge,go down about 1 mm and then gently away with the dremmel. This little machine is easy to mod up,it'll look nice with an RCA-post pictures when you've sorted it.
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