I was making a couple custom amps this last weekend and realized how much I rely on my drill index.
It is like the one pictured above and has both metric and imperial sizes. I find this to be most helpful when using recycled / repurposed parts. It is my secret weapon for final fit and finishing on most projects. I don’t think I have run across a bolt or screw or dowel pin that I did not have the correct size.
So do yourself a favour and make a good quality drill index a must have piece of equipment for your shop.