Overall width is 18.5"
The front pieces are 4.25" wide with a 10 gap between them for the front grill.
6.75" depth.
Front edge is right at 2" tall
Rear edge at back is 1.4" tall.
https://photos.app.goo.gl/Cdbu6ra8VIDLmQxA3
My BK photos, some decent shots that may help you along getting the neck remade.