I feel your pain......here are a few things I have learned in the 5 years I was in sales selling building products to local and national builders. If you/your company/ an employee/ a delivery man either sends the wrong item, damages the item, or relays any information that leads the customer to having a failure, installation of wrong product, or misuse of a product for the improper application.....then you do one thing and only one thing!!! you replace the product and do it so in a very timely fashion, no unfortunately in my line of work, labor never ended up getting replaced or compensated. o that one ends up being written off as a loss, I know it sux the big one, you depend on a reputable company to supply you with all the products to complete a certian task or job and if they mess up the item(s) and you have a faliure of some sort as a result form that, well unfortunately the company has a name to uphold and a product to stand behind along with their employees. Stand firm, I see no reason why a company like Weisco would not replace the block/pistons and any other items proven to have failed due to their shipment of the wrong product. Good luck!!