Doing it right the first time

Look at the piston that came out of that bore and see if there are any dark grey oval or circular areas on the thrust faces.... it almost looks like the piston scuffed. The 'dribbles' on the cylinder wall would be some sort of etching as a guess.... did this sit a while? Or a lot of grit got in there.

Looks like the bearing saw a bit of heat (from oil starvation?) but the pix is not too clear.