Is it realistic for a homebuilder to rebuild his own Lycoming IO-360? I am building a Cozy aircraft and I am thinking about engine issues. New engines are expensive. The run out engines look pretty cheap. I really like engines and engine work, but I have never worked on an aircraft engine. I have rebuilt a few motorcycle engines. In my experience rebuilding an engine is just about following the instructions step by step. Do many builder do their own rebuilds?