Is there any method to add a 3D Solid to Custom Stringer in Stair Style?

[jtm2020hyo]

I did not found a method to add a 3D Solid using the Body Modifier command but does not appear in the Stair Component list:

PD: attached file

[R_Tweed · Accepted solution]

No.  I find it easier to use mass elements or sweep a profile and use that in place of the the stringers. I'll use the stringer as housed or full slab to enclose the underside as a quick run, but when I want detail, I make them separately.