Finally getting around to rebuilding/restoring my 97 SPX. I have decided to go with Pro-X pistons and am going to send the crank out to be rebuilt. Can’t find much on the rotary shaft and counterbalance shaft so looking for guidance there. Would prefer to have them rebuilt/replaced but don’t know where to go for that. It’s going to be a long and expensive process but I’m excited to finally get this thing looking new.