Cut Replacement Door Bottom?

Yes, you could cut down the 58-176 to a desired size with a fine-tooth hacksaw, like our 75-023A.  We have had past customers use this sweep for exterior French doors; it's a pretty versatile sweep that works with a variety of doors, which is why it's my favorite of the ones we carry. Finally, this will cover a gap up to 1/2". Let me know if you have any other questions.