well two more bolt holes in the mains of a weak block to start with . stud the two bolt main use a main girdle . splayed would work .but buy caps.. fit the caps . line bore block . then deck with BHJ tru-deck .then bore hone block with deck plates .now you want to push this block to ?? how many Hp 550 it should hold it but if your going to go with the block work you may want to look at a SHP dart block