The pictures I have seen show the 2 cast boss on underside with what appears to be correct stamping from Offy. But the casting also has the 4 areas where the metal plate normally mounts. Plate is not there, but there are no signs of the 4 mounting holes ever being drilled. Has the S1MS casting with temp, heater and PCV ports. Trying to determine if authentic or really close repo. There are no holes in the 2 boss areas nor are there holes where metal plate would mount.