Cheers, supporting the fender while drilling can be tough, just find something that roughly approximates that shape, put it in a vise and lay the fender over it.
Drilling inside to out (through into some wood) made the most sense to me. Use a countersink to deburr the hole after.
You're right, it's been awhile...
@hamrack started
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Cheers, supporting the fender while drilling can be tough, just find something that roughly approximates that shape, put it in a vise and lay the fender over it.