Locks can be a bit tricky to install well on boxes and cases. They typically require multiple mortises of varying depths, and things don’t always line up quite right. Measuring can work, but I find it best to use the lock itself to lay everything out. Here’s how.
I’m not a big fan of shiny hardware. So, most of the time, I don’t use hardware as it comes right out of the package if it is shiny and bright.