I don't have the cabinets yet and need to figure out how to rough in a box for under cabinet lights.
First, is it OK to splice off a 20A circuit dedicated for the range hood to serve these under cabinet lights?
Second, where is the best position (height from floor) for the rough in box? Those are typically low voltage right? How are the wiring between those lights handled? Do you run them behind wall then out to the light and back into the wall...or are the wiring just concealed on the underside of the cabinets?
The answer to your first question is....maybe. It would depend on if the hood is cord/plug connected.
The answer to your second question is again a little dependent on what you buy. I rarely installed low voltage undercabinet lighting...however, that was before LED's becoming more common place.
We stubbed out NM at about 56" and hardwired the fixtures tight to the wall. Be careful, not all low voltage wiring is rated to be concealed. When I did install a low voltage system, we ran NM up the wall and changed over to low volt cable in a tiny JBox where it come out of the wall.
Answers based on the National Electric Code. Always check local amendments.