Sure looks like it... I checked them out and the rods are numbered to each cylinder, and are turned right on the crank side, and by looking at the valve reliefs the intake relief is the larger one. The pistons sure look like they are upside down to me.. But turning them over and installing them the rods would be wrong as far as the tangs (always to the pan rail side. and the bevel facing to the outside of the journal... I told him to wait and see what was said.
These are B1 Originals pistons, and this is my engine, a friend is assembling.
Pretty sure they are upside down.