It doesn't look like your V-notch intersects the vacuum connection. If not, I'd drill a hole near the bottom of the V-notch to connect them. You could use a sheet plastic or metal gate to laid over the large hole in the end to increase draw at the V-notch, or a smaller gate to block it off so the larger hole draws air better, and make it even more versatile.

For cheap bastriches like me, it could be built as a pine box from scraps so you could avoid using a nice piece of solid cherry wood... Would make cutting the holes a bit easier, too.

Bill