OpenComputers Addon with a Block Replacer
Place down the block, attach it to a computer network and insert blocks into the side of the replacer using a hopper, pipes etc.
Call .replace(posX, posZ, negX, negZ, y, block) where all the coordinates are relative to the replacer block and the replacer will use the block from the internal storage and replace all blocks of type 'block'. You can then pull the replaced blocks out of the bottom of the replacer.
