Hi,
I was trying to get your seam and ran into a chanfer problem area.

I swept a profile to get the rough shape. (just an experiment so the shapes are primitive)

I seperated the piece with a boolean and then wanted to chamfer to create seam look.

On the top piece, front side, there seems to be 2 lines where I would expect the one to chamfer.

This is my holdup to get this front line to appear seamed.

If anyone cares to look at it and input, that would be nice.

I think the chamfer would not be the finished option for the model, I was just using it for fast look.
Maybe I should just dump it for this application and go with actual step back of edges.

Burr