Metal Chimney Pipe Flashing for Ribbed Metal Roof

Hi Folks... I'm installing a woodstove in my new room addition.

The cathedral ceiling kit offered by DuraVent comes with a metal chimney-pipe flashing, basically just a flat sheet with a metal cone in the center. I see no way to install this on my ribbed metal roof.

I don't want to lay it atop the roofing and just slobber caulking all over it, as so many want to tell me to do; that's not flashing, that's a patch! And it won't last to awfully long, either.

It's been suggested that I cut a 1/8" slot in the metal roofing, and slide the up-slope end of the flashing into the slot and underneath the metal roofing. Well, yeah, I can see that, but what about the ribs? Installed this way, it's just going to sit in the air, atop the ribs. Am I supposed to shape the flashing to conform to the ribs? Am I supposed to flatten the ribs underneath the flashing?

Still others have suggested a high-temp silicone boot type of flashing... not sure that would work in this application, and I'm not a big fan of boots anyway. And again, it's not flashing; it's a patch, set on top of the roofing and sealed with caulking. I just don't see this as a permanent solution, or even a good one.

DuraVent makes mention of a "Flashing for Metal Roof" on their site, but it's just offered as an option when buying the kit... no explanation of how it differs from a regular flat one, no pictures, nothing. I really don't want to just buy it and charge in blindly, hoping it will be just what's needed.

Anyone have any experience with a similar problem? Thanks!