The 010 ---- 020 means high-nickel, high tin mix. This is desireable. You still have not found the casting # and the date code. Look at the drivers side back of block just in front of the bell housing. Oh ,If you live where You drive right hand drive cars it would be on the left side of the car. There may also be more numbers near the head surface at the top, but they could have been machined off by now.