Is the old stove wired directly to a junction box, or does the cable
come out of the wall and terminate in the stove chassis, or is there a
big ugly brown receptical that it plugs into?

Number B. The flex conduit comes out of the wall.

As the metal conduit serves as ground, I'm just going to tie it there. But
since the wire is also bolted to the same metal box I am connecting the
conduit, it will electrically serve no purpose.