That's kind of the idea I'd like, except that wrench shows a width of about .3"...which should be familiar to us gun people because that's about 7.62mm. The wrench set I linked to earlier claims to be 2mm, which should be thin enough to fit in under the front sight with margin.
It'll be splendid if the Stanley wrench you linked will fit, but I don't think it will. If I'm wrong, that'll be the go-to solution.