My 07 3500hd. Is all apart. Presently doing a frame swap. With the engine out what are somethings I should replace? The truck has 217k on it. Parts of the exhaust have been removed by the previous owner. Other then that I don't really know what else has been done to it. I thought it would be a good idea to replace the head gaskets and other hard to reach parts. Any ideas would be helpful. Thanks