Quote Originally Posted by TimeRender View Post
I'd stick with cutting it completely through. Sink tube isn't terribly thick and your groove would be barely noticeable if you were able to do it at all. Just be sure you use screws in each corner to prevent it from warping.
The sink tube is chrome plated brass. I don't really have to go that deep before the brass shows through from beneath.

But cutting is an option too as it allows more room for the rubber grips.