I want to cut a bevel on a portion of a curved edge, but not sure what way would be best.

I'm wanting the bevel to go from where the triangle is at the highlighted inflectionPointPlane to the triangle at the back of the part. The bevel should start at zero width from the inflection point(basically half the length of the part 30.25") and only have a maximum width of about 4" .I tried using a third triangle in the middle and using a loft cut but it didn't look right. I feel like I have to use a path and a sweep cut, but I am not sure how to make a offset curved path

The bevel will be along, where this sweep cut is.