the valves in the pic look ok, but the pistons look like you had bad detenation. a few of those pistons look like they were pounded by the valves, ie very bad cam timing. were any of the valves damaged. looking at the piston skirts, (sides of pistons) looks like they have very low hours. you can still see the machined lines on them. did you bend any valves or break a rocker or bend a push rod= improper cam timing or builder not clreancing the pistons=putting clay on the pistons, assemble heads, turn over motor and check to see if valves hit the clay. It looks like something broke or came apart. we need to find out what that was. what kind of timing chain, gear drive, timing belt was used? tell me about the builder. what type of shop, What type of work does the majority of the shop do? high performance, normal cars forighn or domestic, boat shop, servicing or motor builds etc? If the builder is offering to repair with out the cost of labor it says something.He knows he did something wrong and is not telling you. be stern, get your new parts from him for free. tell him you know he messed up and you just want the parts and will have a expiernced marine performace motor builder assemble it the correct way. If he refuses then you tell him youl see him in small claims court and will bash his shop by reporting him to the better business burueu. In the mean time lets figure out why your motor broke so you can lean like the rest of us, what not to do as you already are.
