This late-model 351W two-bolt main block has been girdled with a windage tray. It also has a one-piece rear main seal. Marvin blueprinted it to MCE standards, working oil passages and installing restrictor plugs at No. 2 through No. 5 main journals to improve oil distribution. He also notched cylinder walls and pan rails to clear rod bolts, and thoroughly inspected for cracks and other abnormalities. The No. 1 main journal does not get a restrictor plug. As you can see, the craftsmanship is impeccable. Marvin uses Glyptal coating from The Eastwood Company to seal unmachined iron surfaces.