I use a small brass hammer and a block of wood to cushion the blow. Make sure the hole is the right size first! If it's a Warmoth body and your ferrules are standard, they should fit fine. It's also a good idea to relieve the edges of the holes a bit. I use an old dull countersink bit, but don't put it in a drill, just free hand it. You don't want to do much, just break the edges a bit. If the hole is too tight, you can crack and chip the finish.
Light
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