Sorry about all that you had to go through . My standard 26hp Trabantwelt rebuilt motor was a lot better engineered, no shavings or grit anywhere, and the ports and exhaust matched up fairly well. They aren’t tuned ports, but it’s a Trabant, not a race car. I checked the crankcase and shaft, nothing wobbled, before I attached the pistons, rings and cylinders. I lined up the arrows on the pistons (both go forward, folks), assembled the motor, put it in the car, and it started immediately. It has a lot more power than the old engine, and after several months and 4000+ km, it runs great. I don’t drive mine every single day, but 3-4 times a week, about 5-10 miles each time. So far, so good. Next step is to take apart and rebuild the old engine when the weather gets warmer and drier.