It would be great if they had different sizes, but just drilled out the holes and they fit fine. One other thing,they are smooth so you probably should add a drop of super glue when installing, just to make sure they don't come back out.
These are very well-made ferrules. The chrome finish looks sharp, and seems tough.
The price is high, but these are some of the better-looking ferrules on the market.
The only drawback is that they're not gnarled, which would help with anchoring them in the body. A little epoxy and a drill press will get them in perfectly, though.