Easy way to create notched 45 degree C channel bend using sheet metal features?

Banana_Science · April 1

I am trying to create this very simple sheet metal part that consists of some C channel with a notch so it can be easily bent to a 45 degree angle and welded (see image below). A snapshot of this document can be found here: https://cad.onshape.com/documents/b6d9cf4af93457c608dc55da/v/1ee43c82ff64d7a6f45128e0/e/8d638676b088e22343cd5a7f

While the problem seems simple, because the two vertical faces are coplanar, I've had extreme difficulty creating it in a clean way using Onshape's sheet metal features. The final flat pattern I want looks like this. The bend lines are in grey and the order of the bends is in pink.

Some things I've tried that haven't worked:

Extruding the entire part as a solid and using the sheet metal convert feature. This won't work since there's no way to split this highlighted face
Create two separate sheet metal bodies using the same sheet metal feature and then try to join them using the tab feature. This won't work because these two faces aren't coplanar
Create the highlighted sheet metal part and then reconstruct the non highlighted part using a combination of flanges, trims, move faces, etc. This won't work because it leaves a lot of relief artifacts that don't need to exist and weaken the part . It also takes an absurd amount of features to complete.