A:Answer Hi Bjr1,
Proper installation of this Samsung wall oven model starts with the height, width, and depth measurements for the cut-out.
Please refer to pages 6 - 7 of the installation guide I have shared below as there 2 cut-out dimension information for this Samsung wall oven model.
https://downloadcenter.samsung.com/content/EM/202012/20201201103637745/Install_NV31T4551SS_AA_DG68-01266A-00_EN-MES-CFR.pdf
Should you need more assistance, please feel free to get back to us via the following options:
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3. Samsung Community: https://us.community.samsung.com/t5/Samsung-Community/ct-p/us
When you message us, provide us with this reference number 1145095424, it will help our team pull up your information.
Leo