Need Help with Parts with Arcs

I find using the SU arc tool to be simple in a few cases, and utterly frustrating in many others.

I am trying to bring together the arced rail in the bed shown below, with a corresponding short curved section of the vertical leg.

I am struggling with many constructions lines, trial and error arcs, and am wondering if anyone here has a better way.

Shown below is the overall bed design (photos) I would like to achieve and my progress on the model area that is most difficult.

Any comments on how to do this?

Thanks,
Ken

Send me your your model and I'll show you.