Looking for advice. I’m getting ready to build window casings for two vinyl basement windows. The windows have what I think is a 3/4” track around the outside to slide the casing into. is it as simple as this? Doing it this way will leave a lip visible- do I just caulk it, and call it a day? Or can I buy thicker wood for my casings, and cut a groove into the rear edge so that it covers the vinyl so its not visible?

If anyone has photos of finsihed windows with a slot/track like this I’d appreciate being able to visualize the finished product

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