Sidewalk ramp workflow

I am looking for some tips on how to better set up this sidewalk ramp operation. Nothing I’ve tried has worked so far to produce the outcome I need.

So by lofting the graded surface instead of patching, and converting my extrusions to polysurfaces, I am able to boolean the sidewalk, but it fails when I try to boolean the curb.

Hello - please post a file with the parts you are asking about, and some indication of

Is it just a matter of combining all the parts into one?

-Pascal