Assembly tip: Make sure to include a short, 3/8-inch bolt in the upper hole in the right (passenger) front side of the block just above the fuel pump boss. This hole is drilled into the passageway for the fuel pump pushrod and will leak oil if left open.
One of the best things about late-model, one-piece rear main seal blocks is the one-piece oil pan gasket. Just place the gasket on the pan rail and bolt down the pan without RTV. This is reason enough to build a later-model small-block.