a lot depends on the size of the pull, the door height, and overall look.
you said both rails are 4" wide? can you show a picture? 4" seems extremely wide.
these are 2 1/2". are yours wider?
these are 3" rails.
in your pic, it seems a little low.
If your handles were over 6", I'd say fine. but if they're not, then I'd raise them to where the two rails meet in the corner. like this one.
or like this one. I think this position looks the best.
If your handles have an overhang, then put the holes even w/the corner
but others start from the middle of the style. you'll notice that these don't have an overhang like the ones above.
these have an overhang so the hole is actually even w/the corner
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Mixing metals
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