Separate selectors for modal overlay cutout target and popper target

I'm using the modal overlay in my Shepherd tour, but I'd like to point the tooltip at a specific element that's inside the cutout area. Here's an example, I'd like the tooltip to point directly at the orange button. I tried using left-start to move it to the top, but unfortunately no amount of configuration will get the arrow to point directly at the button:

It'd be great if attachTo had an optional second element attribute for either popper target, or the overlay cutout target, so that they can be two separate elements. By default they should both be the same. Not sure if you'd rather an option for each, or go with just one or the other.

Start by tracing the attachTo configuration and the modal overlay, popper target, and overlay cutout behavior described in the issue. Define separate selectors for the popper and cutout targets, while preserving the current behavior when only one target is supplied; done means the tooltip arrow can point to the orange button independently of the cutout.