I think I came up with a reasonably easy solution per this sketch:

https://photos.app.goo.gl/b39g3QRzR78yHutW6

I would add a surface-mounted at the lower level of the step, and this section of panel will be only 4ft+/- on either side instead of the 8ft panels.

The alternative of modifying each panel would be somewhat time-consuming and might not end up looking nice.

Thanks to all for the detailed advice and suggestions.
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