Good save?.I never heard of Kroil til recently?.pretty expensive but well worth it. Any time you can save a block from a 401 you have done well. I had a 455 Pontiac that I literally put 8 sleeves in because it took a sledge hammer to get it apart. Guy had left it in the rain for years and it was original to the car. There were a few cylinders so rusty that I sandblasted them just to see where to hammer. My machinist now has several sets of honing stones that we use before we take any measurements. I believe these 401 pistons are available in increments other than .030 and .060. I am doing a DZ302 and we found some .040 that save it from being bored further than necessary. Hopefully yours will go with minimal oversized.