You should be able to knock them out with a punch. There should be a small hole on the front side of the block in line with the dowels. Install the new ones with a brass hammer or a regular hammer and a block of aluminum or brass. Use some lube and make they start straight before you drive them home.I've got a mark IV bbc. I need to replace the pins for longer ones. How do I get the old ones out and the new ones in? Thanks.